See the full interview with Dr Helmut Marko in the Austrian Grand Prix qualifying show. See the full interview with Dr Helmut Marko in the Austrian Grand Prix qualifying show.

Red Bull are considering manufacturing their own engines after 2015 - but have confirmed they will continue to use Renault power next year.

Red Bull have won all of their previous eight titles in partnership with the French company but have been left behind by Mercedes at the start of the sport's new hybrid era largely because of the inadequacies of the Renault V6 power-unit.

According to Red Bull boss Christian Horner, who has made plain his frustration with Renault since the start of winter testing when the RB10 was beset by reliability woes, the Renault power-pack is around 30 horsepower shy of Mercedes' field-leading engine.

"We will have a look at where the engine is standing after this weekend and then we will see what we can achieve with this engine," Red Bull advisor Helmut Marko told Martin Brundle in an exclusive interview that will be played out in full during Sky F1's coverage of the Austrian GP.

"If we don't see a possibility to be on a same level with Mercedes then we will have to look for alternatives."

In Friday's practice sessions at the Red Bull Ring, the team's two cars were over a second adrift of the benchmark times set by Mercedes pair Lewis Hamilton and Nico Rosberg.

Next season, Honda will return to the sport as one of four engine suppliers alongside Renault, Mercedes and Ferrari.

However, Red Bull's room for manoeuvre is limited. Ferrari and Mercedes are the World Champions' closest rivals, and Red Bull would be loathe to become a 'customer team', while Honda are returning to power McLaren, with whom they enjoyed a title-winning partnership in the late 1980s and early 1990s.

Short of options, Red Bull are thus considering the previous unthinkable option of, in effect, making their own engines.

"We will not be asking Mercedes," Marko confirmed. "But there are a lot of very skilled companies concerning engines. AVL is 70 kilometres from here."

Pressed whether that meant a bespoke 'Red Bull engine', Marko replied: "You should never say no. We are looking at all alternatives."

Following Marko’s comments Horner added Red Bull’s relationship with Renault is reaching a “pressure point”.

“First of all what you have to remember is that Red Bull have won eight World Championships with Renault – we’ve won all our race wins with Renault,” the Team Principal told the F1 Show.

“They are having a tough time at the moment and we are doing our best to try and support them and assist them engineer their way out of this. But a team like Red Bull is never going to be short of options and it is our job and our responsibility and duty to look at all of those options to try and ensure we have the best powerunit going forward. Hopefully that will be with Renault but you have to look at all the options.

“He said Sunday so Renault be warned. We are approaching a pressure point, but we won’t have any other engine than a Renault in the car next year that is 100% certain. But we cannot afford to be in this position forever and Renault are doing their best to respond, but they need to make a step to close in on Mercedes.”

This weekend's Austrian GP is live only on Sky Sports F1. Race Day coverage begins with the Track Parade at 11.30am on Sunday