Jul.5 (GMM/Inautonews.com) All sides came out fighting on Saturday following speculation Red Bull is set for a sensational switch to Mercedes power.

A British magazine earlier reported the engines could be re-branded as Aston Martin, a British luxury carmaker that is 5 per cent owned by Mercedes.

But Red Bull’s Dr Helmut Marko said on Saturday: “Red Bull and Renault will fulfil their current contract until the end of 2016.

“There are talks with Aston Martin — but about other projects. There is also a company called Red Bull Technologies,” he told Speed Week, amid other speculation that Adrian Newey could be involved in a Red Bull road car project.

Marko, therefore, said the talk is just the customary round of F1 rumours.

“At the Red Bull Ring, it was Ferrari, now it’s Mercedes. I wonder who it will be in Hungary. Honda?” the Austrian said sarcastically.

But Mercedes’ Toto Wolff had a slightly different message at Silverstone.

“Aston Martin is a great brand,” he said, “and Daimler has an industrial partnership. But this has no influence on our formula one involvement.

“We are in F1 to promote the brand Mercedes-Benz. What was said in this magazine is something that definitely did not come from us,” added Wolff.

However, he would not rule anything out.

“It is always dangerous to talk about something forever. But the current situation is that we have Mercedes-Benz racing engines, and we will not give them different names for marketing reasons,” said Wolff.

But everything might change if Renault – Red Bull’s current supplier – buys back Lotus, who are currently supplied by Mercedes.

“True,” Wolff said, “if that happens, then we would have the capacity. But there are still a lot of variants that are yet to play out,” he added, also referring to rumours Renault could leave the sport completely.

“If you had asked me a few months ago, I would have categorically ruled out a Mercedes-involvement with Red Bull. But I have to say that as of today, no, there are no negotiations.”

Red Bull team boss Christian Horner has also commented on the rumours, insisting that with so much gossip doing the rounds, “The basic fact is that we have a contract with Infiniti and Renault.

“Anything beyond that is pure speculation,” he insisted.

And Mercedes team chairman said any talk of Mercedes-powered Red Bulls is “rubbish”.