Renault give Red Bull deadline for engine decision

Renault say Red Bull must make a decision over their engine supplier by May. The four-time constructors' champions have voiced concerns over their provider, and have been linked with switching to Honda power after Toro Rosso took on the Japanese manufacturer for 2018.

Red Bull won their four titles with Renault power, but have struggled to match Mercedes and Ferrari in the hybrid era.

Though they have often won the development race through seasons, Red Bull have often had to fight from behind in the championship.

With just three engines available to teams through the 2018 seasons, Renault chief Cyril Abiteboul has said they will focus on reliability before performance - a suggestion Red Bull team principal has issued concerns about.

Toro Rosso made claims that Honda have made strides in improving their reliability and performance after the first day of pre-season testing and it has been suggested that Red Bull could ditch Renault for McLaren's former supplier.

"We are not going to hang around forever,” said Abiteboul told the media.

"I know what Christian is referring to when he says that he has options.

"He is absolutely right. Like him I know and read contracts. There will be a deadline for Red Bull Racing to define what they want for the future.

"I believe it is by the end of May when there needs to be some clarity as to who is supplying which team, which supplier is supplying which customer team. So that as far as we are concerned will be our deadline."