Honda boss Masashi Yamamoto says it is likely the Japanese manufacturer will stay in Formula 1 beyond 2021.

After signing a one-year contract extension beyond 2020 with Honda, Red Bull's Dr Helmut Marko said talks about 2022 and 2023 are already underway.

Red Bull is clearly under pressure to wrap up a longer Honda deal in order to convince Max Verstappen to sign up for 2021 and beyond.

"Mercedes and Ferrari have the same pressure to succeed," team boss Christian Horner insisted to Auto Motor und Sport.

Marko added: "Where would Max go? Mercedes could not afford to have Hamilton and Max together."

Nonetheless, signing up Honda for 2022 and beyond would undoubtedly help Red Bull to secure its future in F1 and the services of Dutchman Verstappen.

"The fact that we have extended the deal by one year does not mean that the project will no longer exist after that," Honda's Yamamoto said in Abu Dhabi.

"We are already engaged in discussions about 2022."

The Japanese insists that rumours Honda could quit Formula 1 were wide of the mark.

"There was no discussion about our participation in F1, but we were discussing how to do our project in the best way," said Yamamoto.

"Now we are achieving good results with Red Bull and Toro Rosso and getting closer and closer to the top.

"Our power unit is still behind Mercedes and Ferrari, but we are much closer than before."

Red Bull and Honda officials have said in recent days that the biggest consideration about 2022 and beyond is whether the FIA will better control engine costs.

At the same time, Red Bull needs to consider signing up with F1 for the 2021-2025 period - without necessarily knowing if Honda is staying too.

"It must be a difficult decision for Red Bull," Yamamoto admitted. "But our discussion about whether we will stay after 2021 is going well.

"We are discussing how we can continue the collaboration and under what conditions."