SALZBURG, Austria -- Carlos Sainz will remain at Toro Rosso next year, Red Bull boss Christian Horner has confirmed.

After seeing his Toro Rosso teammate Max Verstappen promoted to Red Bull ahead of him earlier this year, Sainz's career path looked less certain. However, Horner confirmed Red Bull has taken up its option to keep him at its junior team next year, putting an end to speculation about his future.

"We took up his option earlier this week, so he's committed to Red Bull for the next 12 months and, as with all the drivers, they are contracted to Red Bull Racing and we have the ability to place them where we want," Horner explained. "He is currently at Toro Rosso, which is where we expect him to be next year.

"We had until the end of the year to take up the option and we chose to do it early to put his mind at rest."

Asked if Sainz's current teammate Daniil Kvyat would be replaced, Horner added: "I'd be surprised to be honest with you. Daniil Kvyat is continuing his development and you can see that he is finding his feet now and there is not an obvious candidate knocking on the door at the moment who would warrant that seat.

"It's great for us to have a development programme that is producing talent like Ricciardo, Verstappen, Sainz as well and obviously Daniil Kvyat. We are not short of talent in our stable."

As hinted before, Horner also confirmed Red Bull's drivers are contracted until the end of 2018.

"We are set in Red Bull Racing for the next two and half years, so it is a luxury issue to have."