END OF AN ERA: Red Bull has announced the end of its partnership with engine supplier Renault. Image: AP / Ng Han Guan
Sochi, Russia - Red Bull's drivers put concerns about their team's future engine supply to one side and said they remained fully focused on the season's remaining races.
Two of the sport's current 10 Formula 1 teams are owned by Red Bull but the Austrian energy drinks company has warned it could quit if it cannot secure a competitive engine for 2016 to replace Renault units.
Ferrari looks like the only real option, with champions Mercedes ruling out any deal that could lead to them being beaten by their rivals, but the sticking point has been over what specification they could provide.
Mercedes already supply four teams while Ferrari provide three with engines and cannot be forced under the regulations to take on more.
While a deal with Ferrari is expected, there have been plenty of warnings about what could otherwise happen and Red Bull's billionaire owner Deitrich Mateschitz has set a deadline for the end of October 2015.
Carlos Sainz, who drives for the Toro Rosso team that acts as a feeder to Red Bull Racing: "I just know that the team obviously is working hard, and now more than ever, to find something for 2016.
"Obviously it starts to be a bit late and we need to design all the rear part of the car. When you don't have something at the rear at this stage of the year, it's a bit tricky - but I have full trust that they will come to a solution.
"They (Red Bull) have done a lot for this sport, a lot for F1 and they will end up having a decent engine, a decent package for next year"
Russian Daniil Kvyat, preparing for his home race as a Red Bull driver after graduating from Toro Rosso, said he was just concentrating on the job.
"My job is to try to drive the car that I have as fast as I can and that's what I want to focus on first of all and the other things that are hanging in the air... I think they are up to other people in our team and I trust them 100%," Kvyat told reporters.
F1's commercial supremo Bernie Ecclestone suggested the situation was out of his hands.
"I can't make these people do something," Ecclestone said. "I don't have engines. These people, nobody has done anything wrong. They are following the regulations. It is as simple as that."