Carlos Sainz available for right price as Red Bull confirm Daniel Ricciardo and Max Verstappen for 2018

Red Bull chief Christian Horner has indicated Carlos Sainz is available at the right price - but reiterated neither Daniel Ricciardo nor Max Verstappen can be bought out of their contracts.

Renault have scoffed at reports the Toro Rosso driver could replace Jolyon Palmer as early as next week's Hungarian GP.

But with Verstappen and Ricciardo tied to Red Bull for 2018, Horner has admitted for the first time that Sainz, who is himself contracted to the Red Bull group until the end of 2019, could leave - if the price is right.

"Sainz has a contract with Red Bull and there are two years left on that contract," said Horner. "We value him as an asset and an asset has a value. So if there was a desire from another team to have him, or for him to go somewhere else, something that has a value has to have a price attached.

"If somebody was prepared to make an offer, we would, of course, consider it. But it would need to have a significant value attached because we have invested in Carlos. We are not just going to give an asset away."

On his own team's line-up, Horner was at pains to stress that Ricciardo and Verstappen would be staying.

"They are totally locked in and there is no price that would be high enough for those two," said Horner. "Sebastian [Vettel] probably holds the key to the driver market for the moment but in Red Bull there will be no change to our driver line-up.

"Both our drivers are very happy within the team and happy to be within the team next year. They will be our drivers next year."

However, Horner confirmed that Ricciardo's present deal does run out at the end of 2018 following what will be his fifth season with the team.

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Watch as the two Toro Rossos collide at the British GP Watch as the two Toro Rossos collide at the British GP

A turbulent month for Sainz continued in spectacular fashion at Silverstone on Sunday when he crashed out of the British GP after a collision with team-mate Daniil Kvyat.

The Russian was adjudged to be at fault by the stewards who imposed two penalty points onto his licence, bringing Kvyat to within three of a race ban.

Sainz said at the start of the month it was "unlikely" he would stay with Toro Rosso for 2018 before being 'slapped down' by Horner and reminded of his contractual situation.

It was an altogether more circumspect Sainz who spoke to the media on Sunday night at Silverstone as he denied any knowledge of the Renault speculation.

"Many people are coming to me about this rumour and for me, it's just a rumour," said the Spaniard. "When not one single comment you receive from your bosses, who are actually managing your career, comes from them then you expect it to be just a rumour. I don't comment about rumours.

"I have not asked yet because I haven't had time to speak with them.

"After Austria we cleared everything, we clarified everything - what was said, what was not intending to be said. We explained to each other everything and [Christian Horner, Helmut Marko and I] were playing tennis yesterday, enjoying our time. We had a good time, the air is clear. I'm a Red Bull driver, inside the Red Bull programme, covering for Toro Rosso next year and looking forward to changing today's result in Hungary with Toro Rosso.

"I think there was a bit of confusion [over what was said in Austria]. I've learnt from it. As a 22-year-old driver, you learn from these kind of things. The air was clear immediately once we started our conversation in Austria and at that point, it was forgotten."