Dennis, right, signed Hamilton aged 13 and built an empire at McLaren before his sad departure this week

Ron Dennis is considering a multimillion-pound legal block after refusing to buckle in an ugly boardroom row that threatens to end his 35-year control of McLaren.

He is mulling the next step in a confrontation that has divided one of giants of Formula One after rival shareholders moved to axe the chief executive against his will this week.

Dennis was voted out of the company that he took over in 1981, even though senior executives prepared an internal document, known as a “risk report”, on the consequences of his departure and concluded that McLaren might lose sponsorship deals worth as much as £160 million. That could be “catastrophic” at worst, they claimed.

That finding will come as a bombshell inside McLaren, where staff at the