Horner: Situation is critical because we don't have an engine

Time is running out fast for Red Bull in their quest to secure an engine supply for next year and team boss Christian Horner has admitted the the situation is now critical.

Horner told Sky Sport, "The current situation is quite critical because as we sit here we don't have an engine."

Red Bull and Renault, a partnership that enjoyed tremendous success from 2010 to 2013, have a deal until the end of 2016 but a bitter couple of years have led to an irreparable situation and it is almost certain that both parties are going separate ways beyond 2015.

Renault have not produced a F1 power unit capable of challenging for wins, and have been plagued with problems as they have been forced to play catch-up with Mercedes and Ferrari without much success thus far.

Ferrari and Mercedes appear to be the only options for Red Bull to source a supply of engines, but this would only guarantee them engines and most probably not A-spec which the works team would use.

"Since the power unit regulation change, it's a very different world that we're living in," Horner pointed out. "There's really only two engines out there that you can compete for grand prix victories with and, unfortunately, Renault have fallen behind that."

"It looks like it's going to be at least two to three years before [Renault] can be in a position to compete again. As a paying customer, we can't afford to wait that long," declared the Briton.

When asked if the very public spat between Red Bull and Renault would deter other engine partners inking a deal with the Milton Keynes outfit, Horner replied, "I doubt it."

And added, "Perhaps we have been guilty of being honest, whether that is my comments or Adrian Newey's comments or Helmut Marko's or most important of all Dietrich [Mateschitz]'s as he is paying the bill at the end of the day."

"I don't believe that would have an impact on influencing any other supplier," concluded Horner.

The Red Bull organisation's first victory in Formula 1 was when Sebastian Vettel won the 2008 Italian Grand Prix with a Ferrari-powered Toro Rosso.

After taking over Jaguar in 2005, their first year as a fully fledged F1 team, Red Bull were powered by Cosworth. The next year they had Ferrari engines and in 2007 began their partnership with Renault.