MEXICO CITY, MEXICO - OCTOBER 26: Sergio Perez of Mexico and Force India in the Drivers Press Conference during previews to the Formula One Grand Prix of Mexico at Autodromo Hermanos Rodriguez on October 26, 2017 in Mexico City, Mexico. (Photo by Clive Rose/Getty Images)

It's Red Bull or bust for Sergio Perez as he fights for one of the last remaining seats on the 2021 Formula One grid.

Perez finished second in a rain-sodden Istanbul Park and is enjoying one of his finest seasons, currently sitting fourth in the Drivers' Championship.

However, he remains without a seat for 2021 after Sebastian Vettel was signed on to replace him at Aston Martin (formerly Racing Point), while Red Bull's second seat is still up for grabs.

Their current driver Alex Albon still remains a favourite to retain his seat, but his 2021 campaign has been underwhelming as he sits ninth in the Drivers' Championship – a full 100 points behind his teammate Max Verstappen.

Perez's former teammate Nico Hulkenberg has also been widely slated for the seat, after two top-10 finishes as a stand-in for both Perez and Lance Stroll this season.

Perez told Autosport that he would only stay in F1 with a team that can compete.

“There's only one option… I want to keep going, I think I'm at the peak of my career,” he said.

“But I also want to keep going with a reason… if there's not a good project that keeps my motivation to give 100 percent, I'd rather not take it.”

If he fails to secure the seat at Red Bull next year, Perez said that he has no interest in looking elsewhere and could be out of motorsport for a year.

“I'm clear on what I want to do, if plan A is obviously to carry on, then plan B will be to stop for a year, see how I feel without racing, see if I really miss it,” he said.

“I have never experienced that (a season without motorsport), my whole life I've been into it.

“I have a lot of interest in other stuff away from racing… I could see myself later on doing other businesses away from motorsport but not in my 30s.”