Red Bull: Carlos Sainz will stay with junior outfit Toro Rosso
|Austrian Grand Prix|
|Date: 1-3 July Circuit: Red Bull Ring, Spielberg|
|Coverage: Radio and live text commentary across BBC Radio 5 live sports extra, BBC Radio 5 live and the BBC Sport website and mobile app|
Red Bull say Carlos Sainz will stay at junior team Toro Rosso in 2017.
Team boss Christian Horner told a news conference in the build-up to the drinks giant's home Austrian Grand Prix that they had taken up a contractual option.
"He is at Toro Rosso, which is where he will be next year," Horner said.
Horner added he would "surprised" if Russian Daniil Kvyat, demoted from the senior Red Bull team in May, was not also retained at Toro Rosso in 2017.
Kvyat was swapped with Dutchman Max Verstappen after the first four races of the season after failing to match up to team-mate Daniel Ricciardo.
Horner added that Kvyat would likely be kept on because "you can see he is finding his feet now, and there is not an obvious candidate knocking on the door at the moment that would warrant that seat".
Horner said Sainz's option had been taken up "to put his mind at rest".
The Ferrari and Renault teams are known to be interested in the Spaniard as an option for 2017.
The decision to take up Sainz's option does not necessarily preclude him leaving, but it does mean that any other team who wanted him would likely have to buy him out of his contract, were Red Bull to agree.
Red Bull motorsport adviser Helmut Marko told Germany's Auto Motor Und Sport last week: "If Ferrari paid, we can talk about it."
Part of the deal that took Verstappen into the senior Red Bull team was a new contract that lasts until the end of 2019. Ricciardo is locked in to the team until the end of 2018.
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