Mercedes' continued participation in Formula 1 could be put to a shareholders' vote at the end of the year.
That is the claim of the respected French commentator Jean-Louis Moncet, writing in his Auto Plus column.
Norbert Haug on Monday denied reports the German car maker is on the verge of quitting the sport because it is not being offered the same Concorde Agreement deal as rival top teams Ferrari, McLaren and Red Bull.
But Moncet's apparently 'well-informed source' said: "The Mercedes directorate will vote on whether to stop the F1 programme at the end of 2012, and consequently (Mercedes) will not sign the agreements offered by Bernie Ecclestone."
The source said "the majority" of shareholders may veto Mercedes' F1 activities, which includes its own works team and the supply of engines to McLaren and Force India.
"The future of the (Mercedes) team is also tied to investment and sponsorship and the outcome of the arm-wrestling with Ecclestone," Moncet's source added.