By Alan Baldwin

ABU DHABI (Reuters) - Mercedes will stay long-term partners to McLaren, the carmaker said on Sunday in the face of persistent talk of them buying a majority stake in Formula One champions Brawn GP.

"There is a very firm decision that we have a long-term commitment to our partner McLaren," Mercedes motorsport vice-president Norbert Haug told reporters before the season-ending Abu Dhabi Grand Prix.

"Rather than going into speculation I have to point out that this team works better together than ever before," he added.

"To discuss other issues and other options that probably are in the background and that are internally discussed is just not the right thing to do.

"The only decision that is taken is that we are firm, here, partners and are connected for a long period of time."

German magazine Auto, Motor und Sport reported last month that Mercedes had agreed to take a 75 percent stake in Brawn within the next three years.

Mercedes have an exclusive contract with McLaren until 2011 so Daimler AG, which owns the carmaker, plans to have major investor Aabar of Abu Dhabi hold the stake in the meantime, the magazine reported.

Daimler management was in Abu Dhabi for the race but Haug played down the significance of that.

"Our board members are here but they certainly are not here to publicly negotiate the future of our Formula One (involvement). It just makes no sense," he said.

"You could do that behind closed doors in Stuttgart or whatever, but you certainly won't do it at the racetrack. That these rumours are going around, fine.

"But my statement again is that we are 40 percent shareholders so Mercedes is a large part of McLaren."

McLaren team principal Martin Whitmarsh reinforced Haug's position.

"Daimler is a 40 percent shareholder...they have been a fantastic partner for 15 years and we are going to be together for a long time to come," he said.

"There is a passionate enthusiasm for Formula One within Daimler. They are going to say, as any business does, what other things can we do, what other options are there to optimise our position"

"I don't consider it as counter to the interests of McLaren. We have a commitment both ways from Daimler to us and from us to Daimler that we are going to be together in Formula One...for may years to come.

"If there wasn't the passion in Daimler for Formula One, then these discussions wouldn't be here," added Whitmarsh, whose team won the drivers' title with Lewis Hamilton last year but struggled early this season.

"A lot of the manufacturers are here almost reluctantly or leaving," he said.

"If you've got one that's hustling in, saying maybe we should look at other options, maybe we should do this or that then that's a passion and enthusiasm for Formula One that makes them such a strong partner."