Team boss Christian Horner has already admitted that, in the last few days before the first test at Jerez kicks off, the 2015-spec Red Bull RB11 car is “not yet” ready.

“There is still plenty to do before Sunday,” he said this week.

Now, Italy’s Omnicorse claims the last 100 per cent Adrian Newey-designed Red Bull may not even have passed the FIA’s mandatory crash tests.

In the not-too-distant past, the crash tests only needed to be cleared ahead of a car’s actual grand prix debut, but now they are necessary even for testing.

It is believed Red Bull is pushing the time limits with 2015 crash testing not due to a problem with the chassis, but simply to give designers and engineers every possible minute to design and develop the Red Bull RB11.

“Mercedes for sure are the benchmark,” Horner said. “They go in as the reigning champions and the favourites for this year and they had a significant advantage at the end of last year.”

Omnicorse said Red Bull, to unveil the car on the first morning of the first test at Jerez on Sunday, will try to pass the FIA tests at the Cranfield Impact Centre on Thursday, leaving just two clear days until the Red Bull RB11’s Jerez debut.

A team spokesman said he is confident Red Bull will be ready for Jerez.

Horner added: “This is probably the shortest production and assembly time in our ten seasons — it is unbelievable what the factory have turned around so far.”