Mercedes F1 competition boss Norbert Haug has again stoked speculation that the team is in talks with Michael Schumacher, by revealing the team may not announce its second driver until after Christmas.

Mercedes has already confirmed Nico Rosberg will drive one of its rebranded Brawn GP cars, but the identity of its second driver remains uncertain.

BMW refugee and former Mercedes protege Nick Heidfeld is known to be waiting to sign for the team, but the delay in agreeing his deal is believed to be because the team is trying to persuade Michael Schumacher to race for it.

Haug told the German news agency DPA on Monday that Mercedes will "have to live" with the Schumacher speculation for now.

"We need time and I cannot promise today that the present will be unwrapped before Christmas," he said.

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