Red Bull team principal Christian Horner is convinced that Honda will produce a “competitive” engine for new partners Aston Martin for the F1 2026 season.

It comes after Koji Watanabe, the president of the Honda Racing Corporation, admitted to select media including PlanetF1.com that the Japanese manufacturer is “struggling” with the demands of the new engine rules.

Christian Horner plays down F1 2026 Honda engine concerns

Additional reporting by Elizabeth Blackstock and Thomas Maher

The F1 2025 season marks the last season of Honda’s highly successful relationship with Red Bull, with the car maker set to link up with rivals Aston Martin for the sport’s new era in F1 2026.

The new rules for F1 2026 are among the biggest changes in the sport’s history, featuring sweeping changes to the chassis and engines including a move to 50 per cent electrification, fully sustainable fuels and active aerodynamics.

Speaking to media including PlanetF1.com at the recent 24-hour race in Daytona, Mr Watanabe raised concerns over the development of Honda’s new engine by admitting that “everything is very difficult.”

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He said: “We are struggling. Now we are trying our best to show the result next year.

“Everything is new. The motor is a new 355-kW, very compact one we need. Also the lightweight battery, it’s not so easy to develop. And also the small engine with the big power.

“Everything is very difficult, but we try our best.”

It is unclear if Mr Watanabe, who was speaking in a second language, was referring specifically to Honda’s progress ahead of F1’s new era or making a more general comment on the challenges of the new rules for F1’s engine manufacturers.

Red Bull have enjoyed a productive partnership with Honda since the pair joined forces at the beginning of 2019, powering Max Verstappen to four consecutive World Championships since 2021.

Despite officially withdrawing from F1 at the end of Verstappen’s first title-winning season, Honda has continued to provide technical support to Red Bull over recent years.

With Honda switching to Aston Martin, Red Bull’s newly established Powertrains division have teamed up with US giants Ford to develop a new engine for the F1 2026 season.

Horner fears that Honda’s F1 U-turn may have compromised the development of its new engine, but is convinced that the manufacturer will still produce one of the best engines for Aston Martin in F1 2026.

He told RN365: “It is a big challenge.

“They disbanded their project and then restarted it again. They may well have lost a little bit of time through that.

“But they’re a very capable company and they’ve got great strength.

“I am sure they’ll have a competitive power unit come 2026.”

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In an exclusive interview with PlanetF1.com at last year’s Abu Dhabi Grand Prix, Horner described Red Bull’s F1 2026 power unit program as “the biggest challenge” the team have faced since arriving on the grid in 2005.

He said: “2026 will be a complete reset, and building your own power unit, four years ago, we had a clean sheet of paper.

“In four years, we built a factory and developed an engine, but we’re taking on 75 years of experience with Ferrari and 30 years with HPP [Mercedes High Performance Powertrains], so we have no illusions.

“The mountain that we have to climb is immense, but with the right spirit and the right quality people that we have within the business it will be achievable.

“It’s by far the biggest challenge that we’ve taken on in Formula 1.”

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