Jenson Button is in danger of being driven out of his team as Brawn GP faces a takeover by Mercedes, the German car giant.

Despite having won the Formula One World Drivers’ Championship last month, Button has been unable to negotiate a substantial pay rise from Brawn and believes that he is being pushed towards a deal with McLaren, to drive alongside Lewis Hamilton.

Even though that would form a “dream team” of successive English world champions, Button has been hurt by the failure of Brawn to come up with a deal he believes would confirm his new-found status.

Sources close to the negotiations say that decisions have to be made within days, but that the talks have been destabilised by reports that Mercedes could announce this week that it is to take a substantial shareholding in the Brawn operation.

From being down and out when Honda, the Japanese carmaker, quit Formula One a year ago, Ross Brawn revived the team under his name to become the constructors’ champions. With sponsors beating a path to the team’s door for next season, the value of the operation has been transformed and could be worth as much as £100 million.

But the casualty may be Button, in spite of his remarkable loyalty to a team to whom he pledged his career and wanted to turn into serial championship winners.

The Somerset-born driver, 29, took a £5 million pay cut to £3 million, but expected recognition of his loyalty after winning the championship.

While Brawn have delayed, McLaren have acted quickly, prompted by Vodafone, their title sponsor, which sees the combination of charismatic world champions in Hamilton and Button as marketing gold dust.

Button was shown around McLaren’s futuristic headquarters in Woking, Surrey, on Friday, meeting senior staff and engineers. McLaren are thought to be ready to bankroll an £8 million salary.

Some observers believe that Button should not attempt to enter a team dominated by Hamilton, who was nurtured by McLaren for a decade before his entrance into Formula One, becoming champion in his second season. But Button is not worried by the competition from Hamilton, who gets an estimated £15 million a year.

He is worried, though, that the switch of Mercedes’s massive resources from McLaren to Brawn may hamper his chance of being in a winning car. He had a ten-season wait before he was given a machine capable of winning the championship and does not want to miss out again.

Button would not be the first British world champion to be ditched by his team. Nigel Mansell, after he won the title in 1992, and Damon Hill, in 1996, quit the Williams team because of rows over pay, believing that Sir Frank Williams had refused to reward their championship performances.

Brawn have offered Button £4 million a year — half of the original deal he signed with Honda immediately before the team was handed over to Ross Brawn.

Button understood that the deal would be restored when the team was on a sound financial footing. But it is not the lack of a pay offer that has disturbed one of the most easy-going men in the paddock.

German-born Nico Rosberg has been signed from Williams for next season and it is widely believed that Mercedes want him as the figurehead of a German-led operation at Brawn. That leaves Button to choose between accepting the deal on the table or moving to McLaren.