Horner must convince Red Bull chief Mateschitz to stay in F1

Senior figures from Red Bull have made repeated threats to quit F1 if it cannot find competitive engines for its two teams once it splits with Renault at the end of this season.

Ferrari is now Red Bull's only option, and Horner said at Suzuka on Friday it is his job to make sure the situation is resolved.

"Dietrich does not speak very often, and when he does you have to sit up and take notice," said Horner.

"He's somewhat disillusioned with F1 at the moment - he's been very consistent in that statement.

"It's my job to try and find a solution.

"We have a commitment to F1, to our workforce, a talented team and I'm doing my best to make sure we find a competitive engine to power the team next year.

"If that is not the case, there is a risk [of Red Bull quitting].

"Red Bull's position is different to Ferrari's, McLaren's, Williams's - Formula 1 has to provide a marketing return globally.

"In order to do that, you have to be able to not be restricted in terms of the tools at your disposal."

Red Bull's quit threats have often been dismissed due to the fact the team is signed up to a long-term agreement to remain in F1, but Horner hinted that would not be enough of a barrier to Mateschitz withdrawing his two teams.

"As Bernie Ecclestone would say, circumstances change," he said.

"The circumstances now look different to when we entered into the agreement.

"Our intention is to find a solution; there is an awful lot of work going on in the background to find a solution.

"Some of that is out of our hands.

"Rest assured every effort is going in to ensure Red Bull will be here until 2020 and hopefully beyond but there are some big questions that need answering."