Wolff urges FIA to take action as Red Bull deny salary cap breach accusations

Mercedes boss Toto Wolff has demanded Formula One's governing body the FIA take robust action over reports Red Bull broke the rules when Max Verstappen beat Lewis Hamilton to last year's world championship. On the eve of the Singapore Grand Prix - a race which could see Verstappen secure his second title in as many seasons - his controversial maiden triumph is under the microscope amid allegations his Red Bull team overspent. F1 introduced a budget cap of 145 million (€148m) last year.

But Verstappen's Red Bull are facing accusations - reported in Auto Motor und Sport and Gazzetta Dello Sport - that they went beyond that figure, potentially by up to five per cent, which would equate to £7m. The FIA are assessing Red Bull's finances with a verdict set to be revealed on Wednesday. Sanctions available to the sporting federation range from financial penalties to a deduction of drivers' championship points.

The latter could have an impact on last season's result. Hamilton was denied a record eighth crown when he was beaten by Verstappen at a deeply contentious winner-takes-all finale in Abu Dhabi on December 12. Verstappen took the title by eight points.

Speaking on Friday evening, Red Bull team principal Christian Horner said he was not aware of any breach. But rival boss Wolff urged the FIA, and its president Mohammed ben Sulayem - elected in the days after the Abu Dhabi fiasco - to follow the rules. "It is of huge importance for a demonstration that these regulations are policed and I have no reason to believe otherwise," Wolff told the BBC.