Niki Lauda insists Red Bull boss Dietrich Mateschitz never seriously approached Mercedes about the possibility of an engine supply because he 'doesn't like' the manufacturer.

Red Bull Racing's future in the sport remains uncertain as it finalises its divorce from current engine provider Renault, leaving it and sister outfit Scuderia Toro Rosso without an engine supply for next season and raising the possibility of it quitting altogether.

Indeed, Ferrari appears to be Red Bull's sole remaining option for an engine supply now after Mercedes' board decided against a deal over fears it would be assisting a key rival as a result.

However, while Toto Wolff has spoken fairly openly about the reasoning behind Mercedes' decision, Lauda has played down the seriousness of the approach in the first place, speculating that Mateschitz didn't show much interest in securing engines because he 'doesn't like' Mercedes.

"It was very clear that Mateschitz never really approached us for the reasons he never really liked Mercedes from the past," he said. "Then Ferrari came and offered an engine which now has negotiations going on over what engines they get

"It is a funny situation. Maybe he is not as interested as he was in the past. There was a long discussion internally, [but] we never got the approach. We don't have to go around and beg people to use the engines. We were never approached, so we never thought about it."

With Mercedes' decision to block a potential engine deal reportedly irking Bernie Ecclestone - who fears it will provide the impetus for Red Bull to exit - , though Wolff accepts the move has had 'political' implications, he is steadfast in the reasons for it.

"This is obviously a political situation that has been going on for a while," he said. "We have made it pretty clear after careful analysis that it is not a route we would like to pursue. We have waited so long to have success with our own works team from when Mercedes decided to go into Formula One and not continue only as an engine supplier.

"Obviously this had a rationale and that rationale is still valid today and this is why we took the decision some weeks ago not to continue."

Lauda, however, plays down the suggestion that Ecclestone has issue with Mercedes, saying 'Bernie is not upset with us about the engine'.

Red Bull says it is still in talks with Ferrari about a potential engine deal, with Christian Horner saying a 'Sauber-type' deal has been mooted.