Ross Brawn should be firing on all cylinders as he returns to the pitwall in Monaco this weekend.

Mercedes’ team principal sat out the recent Spanish grand prix due to illness, but a scarcity of extra information triggered speculation.

One rumour was that he is seriously ill, whilst another was that his absence may in fact be due to his German employer’s high-stakes spat with Bernie Ecclestone.

The latter theory gained traction since Barcelona, with acting team boss Nick Fry taking a much higher than usual profile, including naming Paul di Resta as a possible 2013 successor for Michael Schumacher.

Explaining his absence, Brawn told Bild newspaper: “On the Tuesday before Barcelona I felt unwell so I went to the doctor and then stayed a night in hospital for some tests.

“When I got home, I decided on the advice of doctors to give myself a weekend off, to be sure that I am fit for Monaco,” the Briton said.

Partly because of Brawn’s deputy Fry’s recent comments, and also due to his paltry points tally and his crash with Bruno Senna, rumours about Schumacher’s future have intensified since Spain.

“A lot has been said and written,” acknowledged Brawn, “but we should not forget that we – the team – have let him down in three of the fives races, not delivering the job we should have.

“We must do better,” Brawn, who worked closely with Schumacher during the seven time world champion’s ultra successful Ferrari era, added.

“We saw Michael’s real quality again in the first race, so it’s for that reason that I believe we will see him on the podium this year.”

As for a possible contract extension for the 43-year-old, Brawn insisted: “When the time comes, we will sit down together and talk about the future.

“I’m sure it will become clear very quickly in what direction we will go.”

Formula one is worth about $8 or $9 billion, as the sport’s owner CVC confirmed it has this week sold a 21 per cent stake to new investors.

News of the sale coincided with the launch of pre-marketing ahead of one of the biggest ever sports floatations, data by the financial experts Thomson Reuters shows.

“It’s cheap compared to Facebook,” chief executive Bernie Ecclestone told reporters on Tuesday, confirming that the Singapore IPO looks set to go ahead soon “with no dramas”.

“All the things that have to happen have happened. It will be finished by the end of June,” the 81-year-old is quoted by the Telegraph.

F1′s new one-fifth owners are US managers Waddell and Reed, the powerful Blackrock and Norway’s central bank Norges.

“It’s a great way to start the IPO and lets investors know what they can expect,” said Ecclestone.

The diminutive Briton said he is keeping his 5.3 per cent stake, and staying in charge. His former wife Slavica controls another 8.5pc, the news agency Bloomberg said.

“You might as well have asked Frank Sinatra who he would appoint to replace him,” Ecclestone insisted.

CVC said in a statement that is remains F1′s biggest and controlling shareholder.

Flavio Briatore could be readying to burst back into formula one.

Germany’s Auto Motor und Sport said the ousted and formerly banned Italian is busily writing regulations for a ‘GP1′ championship.

They could be adopted should the FIA not sign up to the 2013 Concorde Agreement, according to the report.

Apparently, the political rumblings in F1 at present are not limited to the sport’s planned floatation, or Bernie Ecclestone’s spat with Mercedes.

Cost-control is also a buzzword. As reported recently, the vast majority of F1′s teams want the FIA to enshrine cost-cutting in the actual sporting regulations, even to the point of pushing for a once highly-controversial budget cap.

F1 chief executive Ecclestone, however, is not famously close with the FIA’s new president Jean Todt, and according to Auto Motor und Sport he is not convinced that the Paris federation needs to write and control the rules.

Enter Briatore. The German report said Ferrari will be a fan of the former Renault chief’s rumoured regulations, as they steer away from the premium on aerodynamics.

Valencia will not be on next year’s F1 calendar, Bernie Ecclestone said on Saturday.

He confirmed that, starting in 2013, an annually alternating deal between the Spanish port city and Barcelona will begin.

Barcelona, the scene of this weekend’s Spanish grand prix, will host the race in 2013, before Valencia returns to the schedule in 2014, the F1 chief executive told Reuters.

Less secure, meanwhile, is France’s touted spot on the 2013 calendar, particularly with the country’s new anti-F1 president Francois Hollande now taking power.

Until recently, the F1 chief executive was saying Paul Ricard was set to join the 2013 calendar, annually alternating a race date with Belgium’s Spa Francorchamps.

As for the state of the deal now, the 81-year-old admitted: “I have no idea. No idea what they (France) are doing.

“It’s a funny arrangement they were making anyway. So I just don’t know.”

Ecclestone is also working on a new deal for the popular Canadian grand prix, having told promoter Francois Dumontier that the Circuit Gilles Villeneuve needs to be upgraded.

“There are two ways of looking at it,” Dumontier, in the paddock of the Circuit de Catalunya, is quoted by La Presse newspaper.

“Either Bernie requires an annual fee windfall, or he will charge a reasonable fee and ask in return for investment in the infrastructure.”

He said the contract on the table is for 10 more years, taking Montreal’s existing deal through 2024.

Ecclestone said on Saturday that he is sure an agreement will be reached, because Canada is one of F1′s most loved destinations.

“I remember saying to Bernie, ‘New York, Austin, I don’t know why you want to go there. Your sure bet is Montreal’. He knows that.

“He’s been in Montreal for 34 years. And in the 22 years of the grands prix in the United States, they’ve had eight different cities.

“He said ‘You’re right’,” added Dumontier.

Another rumour, repeated by The Times’ Kevin Eason on Saturday, is that the planned 2014 Russian grand prix in Sochi “is doomed”.

Bernie Ecclestone claims he is close to reaching an agreement with Mercedes over the future of the German marque’s involvement in formula one.

The parties have been at loggerheads over the F1 chief executive’s refusal to offer to Mercedes the same Concorde Agreement deal reached with other top teams Ferrari, McLaren and Red Bull.

In response, it has been suggested not only that the situation threatened the sport’s floatation plans, but that Mercedes could sensationally quit F1 at the end of this year.

“We are now 80 per cent there,” Ecclestone told the German newspaper Bild am Sonntag in Barcelona.

“The other 20 per cent, we will get there soon,” he added.

“We have spoken with several Mercedes managers. I am sure we will see more of Mercedes in formula one.”

Bild said the deal being discussed between Ecclestone and the Stuttgart based carmaker will see Mercedes in F1 at least through 2020.

Norbert Haug, however, sounded surprised.

“I have to apologise, but we don’t want to give any information at the moment about the state of the negotiations,” Mercedes’ motor racing vice-president insisted.

A lack of official information has triggered speculation about Ross Brawn’s health.

And another rumour is that his absence in Barcelona could be connected with Mercedes’ billion-dollar dispute with Bernie Ecclestone over the next Concorde Agreement.

The German squad announced on Thursday that Bob Bell is leading the team in Barcelona because regular boss Brawn is back in Britain on doctor’s orders.

Bild newspaper said the 57-year-old was given the advice in hospital earlier this week, following a dizzy spell at his home in England.

“It’s more than the flu,” chief executive Nick Fry is quoted as saying, “but I can assure you that it’s nothing life threatening.”

Indeed, a spokeswoman told us on Thursday that Brawn will be back to work at Monaco in a fortnight.

For Spain, Brawn will watch the action on television.

“We will still keep in touch,” Michael Schumacher revealed. “Ross cannot be replaced. That’s simply impossible.”

F1 needs to resolve its dispute with Mercedes before the sport’s multi-billion dollar floatation plans can go ahead.

That is the warning of the German team’s chief executive Nick Fry, as Mercedes refuses to sign up to the new Concorde Agreement because rival top teams Ferrari, McLaren and Red Bull have been offered better deals.

Fry is quoted by The Times newspaper as admitting that the progress of talks with Bernie Ecclestone are “not as strong as I would like”.

But he warned: “If CVC wish to float F1, I think they need this resolved fairly quickly — possibly more than we need it resolved.”

At the same time, he played down speculation Mercedes is on the verge of quitting F1.

“The mindset is absolutely in capital letters: Mercedes-Benz wishes to be in F1,” Fry insisted. “I would add that F1 also needs Mercedes-Benz.

“I am completely convinced in my mind that if CVC wish to sell some or all of F1, the value they can derive from that would be severely diminished if Mercedes was not a participant.”

But a senior executive of Mercedes denied the spat is about money.

“It is about fairness,” the unnamed official told The Times’ Kevin Eason.

“We are facing a situation in which three teams will between them decide some of the biggest issues in formula one. That cannot be right.”

Montreal has been warned to spend around $15 million on the Circuit Gilles Villeneuve or risk losing the Canadian grand prix.

La Presse reports that Bernie Ecclestone has said only a major redevelopment of the circuit will lead to talks about a new contract beyond 2014.

The report said that, in light of the F1 chief executive’s warning, Montreal mayor Gerald Tremblay has appealed to higher levels of government for the necessary money.

“Negotiations are underway between the three levels of government and the bodies of formula one”, the report said.

Race promoter Francois Dumontier told RDS: “It’s premature to talk about this.

“There are still two years to go on the current contract. We have started talking, but that it’s out now I find excessive. Honestly, I don’t know where it’s come from.”

He added: “Given that the permanent installations of the circuit, including the control tower and the garages, are nearly 25 years old, it is likely that their repair is an important element in the negotiations for an extension to the current agreement.

“But it seems to me to be premature to talk specific sums.”

Magny Cours is still in the race to host France’s return to formula one.

But according to RMC, the race’s former host – having run the French grand prix between 1991 and 2008 – has been handed a much higher price-tag than Paul Ricard.

Just before Nicolas Sarkozy lost the recent presidential election, the basis of an agreement to annually alternate a French GP with Belgium’s Spa Francorchamps was agreed.

The 2013 host would be Paul Ricard, the Bernie Ecclestone-owned circuit, and the race fee EUR 22 million.

Politics, it seems, have intervened.

Francois Hollande, France’s new president, is not a supporter of the grand prix, and vowed to re-evaluate the sport’s return to the country.

RMC reports that officials at Magny Cours have used the opportunity to “repeatedly” contact F1 chief executive Ecclestone in recent days.

The Nievre region is politically aligned with the new administration, but Ecclestone is reportedly “asking EUR 10 million more” for a race at Magny Cours.

Politics, however, could also be on Paul Ricard’s side, with Citroen’s former world rally boss Olivier Quesnel reportedly lined up to lead the F1 project.

Quesnel is reportedly close to FIA president Jean Todt, and the pair apparently met earlier this week.

Michael Schumacher has been pipped at the post in the race to be the world’s richest sportsman.

According to the Sunday Times’ annual listings, the seven time world champion’s (US) $823 million in career earnings is beaten only by golf legend Tiger Woods.

American Woods has earned $869 million in his own ultra-successful career, the newspaper found.

And the Sunday Times said the pair have each earned hundreds of millions of dollars more than other high-earning sportsmen, including Michael Jordan ($516m), Roger Federer ($316m) and David Beckham ($258m).

F1′s two other representatives, Fernando Alonso and Kimi Raikkonen, were way down the top-twenty list, with their respective earnings at about $161 million apiece.

McLaren’s world champions Lewis Hamilton ($89m) and Jenson Button ($85m), meanwhile, appear only on the list for British sportsmen, and they are both outpaced by the $129m earned by former Ferrari driver Eddie Irvine mainly through property investment.

However, Hamilton and Button have each earned more in their careers than David Coulthard, Nigel Mansell, former BAR boss David Richards (all $80m) and Sir Jackie Stewart ($67m).

Those earnings, however, are all dwarfed by Bernie Ecclestone’s estimated $4 billion, although the 81-year-old F1 chief executive does not appear at all on the list of the world’s richest overall.

That list is headed by mega-earners like Sauber sponsor Carlos Slim, who according to the Sunday Times is worth $71 billion.

Bahrain, the controversial island Kingdom, could have been central to McLaren’s decision to agree the terms of the next Concorde Agreement.

Bahrain’s ruling family, through its investment arm Mumtalakat Holdings, owns half of the famous British team.

The Times’ F1 correspondent Kevin Eason quoted a source as saying the link “pushed (McLaren’s) Concorde deal over the line”.

In return for signing up, Bahrain reportedly received a “pledge” that last month’s highly contentious grand prix would go ahead.

Eason also said it is possible that one of McLaren’s two Bahraini directors, rather than the obvious choice Ron Dennis, could be appointed to the F1 board once the sport is floated on the Singapore exchange.

Bernie Ecclestone denied the 2012 Bahrain grand prix and the Concorde Agreement deal were linked.

“It was nothing to do with the Bahrain race (going ahead),” the F1 chief executive insisted. “But McLaren liked the deal.”

Intriguingly, however, F1′s post-stock market floatation chairman Peter Brabeck-Letmathe has defended the controversial decision to push ahead with Bahrain last month.

“The race was exploited by the opposition in Bahrain, not vice versa,” he told the Austrian newspaper Kleine Zeitung. “That was not interpreted correctly by the media.

“If groups want to exploit sporting events for their interests, then the worst thing you can do is give way.”

Brabeck also compared Bahrain to England.

“In what countries are there no riots?” he asked rhetorically. “A year ago there were riots in London — should the Olympic Games now be cancelled?”

Mercedes is “on the verge” of quitting formula one.

That is the alarming claim of the London newspaper The Times, in an article written by its authoritative F1 correspondent Kevin Eason.

Eason wrote that while rival top teams Ferrari, McLaren and Red Bull will get to appoint directors once F1 is floated on the Singapore exchange, Mercedes has not been extended the same offer.

“Why should Mercedes have the same deal as the others?” F1 chief executive Bernie Ecclestone is quoted as saying. “What have they done in formula one?

“They won a race and that is it.”

That attitude, Eason argues, has left Mercedes “on the verge of quitting formula one”, having apparently conducted a study into how its Brackley based works team could be withdrawn.

Eason also quoted Ecclestone as having “scoffed” at the suggestion Mercedes quitting could wipe 20 per cent off the value of F1′s stock market floatation.

Food giant Nestle’s boss has confirmed he is set to enter the world of formula one.

Austrian businessman Peter Brabeck-Letmathe confirmed to Kleine Zeitung newspaper that he has been lined up to chair the sport’s parent company once it has floated on the Singapore exchange.

“That’s right,” said the 67-year-old.

“And it’s true that I have agreed to take over the chairmanship of the supervisory board in a non-executive function.

“If formula one is to be a public company then it is important that the chairman is independent.”

Brabeck-Letmathe confirmed that Bernie Ecclestone, 82, is remaining F1′s chief executive.

“We certainly hope that Bernie stays healthy for a long time and can keep on working,” he said.

“I am already impressed with his performance. But of course it is the task of a supervisory board to ensure the succession of a business.

“At Nestle, I have always ensured that everyone can be replaced from the executive board within 24 hours. So we need to think about how to replace Bernie Ecclestone as well.”

An obvious tension was evident at Mugello when Pirelli’s Paul Hembery was asked about Michael Schumacher.

The seven time world champion had slammed F1′s official supplier after Bahrain, arguing that the 2012 tyres degrade so quickly it makes driving a grand prix car as slow as a safety car.

“We haven’t spoken,” Briton Hembery is quoted by Germany’s Auto Motor und Sport. “I’ve just read something on the net about the tyres from his teammate Nico Rosberg which is very different.”

Asked if Schumacher’s criticism was irritating, he answered: “We built the tyres the way we were asked to.

“The FIA, Bernie Ecclestone, even the teams wanted it this way. The spokesman for the teams at the time was Ross Brawn, Schumacher’s team boss.

“There have been four different winners in the four races so far, which alone shows that we must have done something right,” Hembery insisted. “As a fan I would be thrilled.”

Asked if he can at least understand Schumacher’s frustration, he continued: “The four winners this year have not won by chance.

“They were absolutely the best drivers in those races and all of them were faster than their teammates.

“I can understand that Michael was frustrated at the last race. Among the four winners so far were two Germans, and then you had Kimi (Raikkonen), who in the fourth race of his comeback is on the podium.

“Racers are winners; they’re not happy unless they’re winning.”

Hembery denied that tyres have, in 2012, become more important than the cars or drivers.

“That’s a misconception,” he insisted. “The driver has a huge impact.

“Anyway I’m convinced that at Silverstone at the latest the teams will have the problem under control. Just as they did last year.”

Finally, he insisted that Pirelli is not going to make any knee-jerk reactions.

“If there are 23 drivers satisfied and only one dissatisfied, then I don’t think we need to change something,” Hembery is quoted by Bild newspaper.

Ferrari’s Fernando Alonso, however, acknowledged a slight frustration.

“For the top teams it’s a bit frustrating,” he told La Stampa newspaper, “when it’s difficult to exploit all your potential.

“It’s like Real Madrid, Barcelona and AC Milan suddenly playing with the budget of Cesena.”

The French government is dashing to seal the lid on the country’s return to F1.

Bernie Ecclestone has said a deal has been reached to annually alternate a race between Paul Ricard in France and Belgium’s fabled Spa-Francorchamps.

But the final signature and official announcement are still missing.

David Douillet, the French sports minister, told Le Journal du Dimanche that the chance France will be on the 2013 calendar is “90 per cent”.

“The contract is going back and forth between the lawyers. I hope I get to London to meet with Bernie Ecclestone between Wednesday and Friday,” he added.

The newspaper said Douillet is dashing to complete the deal by this weekend’s presidential election, because socialist frontrunner Francois Hollande has hinted the grand prix project would be reviewed if he is elected.

Douillet admitted that it is “very likely” Hollande would “bury” the race.

Le JDD newspaper said organisers and Ecclestone have agreed the race sanctioning fee, EUR 22 million, which is still a few million short of guaranteeing a balanced budget.

And “without a balanced budget, we do not sign,” he warned. “The state, which does not participate financially, is still the guarantor of any debt.”

There also remains an odd silence from the Belgian side, who have not confirmed that Spa is the circuit that will alternate with France.