Red Bull boss says Renault has "guaranteed" total engine parity with works team.

Despite the fact that neither of the Red Bull owned teams appears to be prepared to be seen sporting the Renault name in public, the French manufacturer is doing all that it can to avoid a repeat of the issues that almost resulted in the pair leaving the sport.

As Renault produces an all-new engine that will start off conservative but then be aggressively developed, the French manufacturer has assured Red Bull that despite wanting to see its own team progress, the Austrian outfit will have total parity with the works outfit.

"We have the guarantee of absolute parity," said Christian Horner, according to Motorsport.com, "and setting that benchmark is great for them to be able to evaluate themselves against.

"They are in a building process and will therefore have an immediate reference of what their engine is capable of," he added.

Despite being one of the driving forces behind the introduction of the new hybrid formula, Renault was caught on the back foot, and while the French manufacturer was effectively best of the rest in 2014 its issues the following season tested the relationship with Red Bull to the absolute limit.

However, on the back of a significant improvement in 2016, coupled with a return to the sport as constructor, Horner believes the French manufacturer has benefitted from the experience.

"I think things have changed internally on the engine side," he said. "After the difficulties we had last year, that was actually the catalyst for positive change and that change has happened, and the benefit we are starting to see over the course of this year.

"So long as that continues then hopefully it should put us into an area within the next twelve months of where we were with the V8s," he added, "within a couple of percent of the best engine. And as far as their own team is concerned, I think we are a great benchmark for them."