Mercedes Motorsport boss Norbert Haug is refusing to join Formula One rivals in threatening to boycott next season's championship over the budget cap.

Ferrari, Renault, Toyota, Red Bull and Toro Rosso say they will quit unless FIA president Max Mosley ditches plans for a £40million annual spending limit.

The teams fear it will create a two-tier Formula One with those adhering to the voluntary cap being given greater technical freedom.

Haug, whose company owns 40 per cent of Lewis Hamilton's McLaren team, maintains that pulling out of F1 "is not a topic at Mercedes".

It is thought Mercedes do not want to be heard criticising the FIA after the organisation took a lenient view on McLaren last month over the Liargate scandal. However, Haug can appreciate Ferrari's stance and is keen to see the row resolved, with Mosley due to meet the teams tomorrow.

"I know that Ferrari have thought about this threat very well," said Haug. "After 60 years in Formula One they would not do so without some serious thinking. We will try to help to find a solution. All the teams are agreed that there cannot be two regulations in one series."