Red Bull are driving in their “own world”, seven-time world champion Michael Schumacher said on Thursday ahead of this weekend’s Turkish Grand Prix.

Former double world champion Fernando Alonso also admitted it would be difficult to stop the Red Bull duo of Mark Webber and Sebastian Vettel on Sunday.

Red Bull lead the constructors’ championship and Australian Webber, who has won the last two races, and German Vettel are joint level at the top of the drivers’ championship on 78 points.

Schumacher, who has returned to F1 with Mercedes GP after three years in retirement, said “When you see the position we are in, Red Bull are driving in their own world.

“After that it’s Ferrari, McLaren, Renault and ourselves but I hope our development moves us closer to be in a reasonable position to fight.”

Red Bull have updated their car for Turkey where the track is expected to suit the its aerodynamic setup as it did three weeks ago in Barcelona.

Ferrari’s Alonso agreed with Schumacher that Red Bull look unstoppable in Turkey.

“It’s the feeling we all have,” said Alonso, who is three points behind the Red Bull pair.

“I don’t think Michael will be able to make the top six in Turkey let alone the podium.

“Red Bull were one second ahead in Barcelona and there will be no magical surprises here. They are clearly ahead of everyone and are leading both championships so it’s up to us to catch Red Bull as soon as possible.” Webber, however, warned against over-confidence.

“We were competitive in Barcelona but I think it will be hard to do that again,” he said.

He added: “We saw last year that cars that were flying at the start of the year slowed down and were exposed by the end of the season, so we’re conscious of that.” Practice session for Sunday’s race are on Friday, with qualifying on Saturday.

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