It emerged in recent days that the German marque's board of directors met and discussed whether it should supply the powerful 2.4 liter V8 to another team.

Mercedes already powers its own Brackley based team as well as McLaren and Force India, but it is known that Red Bull is open to moving from the Renault stable.

But Mercedes GP team principal Ross Brawn was quoted earlier this week as suggesting a fourth engine customer might be too much.

"That is correct.  We also have KERS, possibly, again next year.

"It would be definitely very difficult for us to equip a fourth team, even if there is no decision taken yet," said Mercedes' competition director Haug.