Rival teams are reportedly unhappy with Ferrari's new alliance with the 2016 entrant Haas.

Ralf Bach, says the two parties are working hard to skate as closely as possible to the current rules forbidding 'customer cars'.

For its part, the American outfit Haas, already a Ferrari sponsor through Gene Haas' machine tool company Haas Automation, is not hiding the extent of the collaboration.

"Of the teams that came into the sport in the last decade only one is left, so we thought it through and came up with some quite different ideas," team boss Gunther Steiner told F1's official website.

"You cannot do more of the same if the recent past has shown that more of the same doesn't work," he added.

Therefore, Haas is not only using a Ferrari power unit, but everything that can legally be bought from the Maranello team -- including use of the wind tunnel.

That came under the scrutiny of the FIA recently, but ultimately got the green light.

Perhaps suspecting that 'customer car' teams are now possible through the back door, it is rumoured that is why Mercedes is currently in talks with Manor about a tie-up for 2016.

And correspondent Bach reports that Red Bull also made a similar effort recently, but Christian Horner's GP2 team Arden was not given an entry by the FIA.

"One thing is clear," wrote Bach. "The competitors are furious with the Scuderia's move."

For instance, Bach claims that on 31 October, Haas will lay off 70 staff, all of whom will then return to work at Ferrari on 1 November.

Asked if Haas is effectively a Ferrari 'B team', Steiner said: "It is difficult to say percentage-wise, but it is going in that direction.

"But don't get me wrong, we still build our own chassis and bodywork."

He said the Haas-Ferrari relationship is a bit like industrial partnerships in the world of road cars, where separate marques share a platform but "keeps their own identity".

Steiner said: "Times have changed. Now nobody cares where you get your steering racks from or your brake pedals.

"But then I also agree that plain customer cars could be dangerous because you might end up with too many of the same cars -- because everybody, of course, wants the best car," he added. "But if you do your aero development yourself it is a good compromise at the moment."

(GMM)