Toto Wolff and Christian Horner are again on opposite sides of the fence over an F1 matter, this time concerning the 2026 engines and the possible returns of V10s.

The Mercedes and Red Bull bosses have sparred plenty of times over the years with the two being the longest-serving team principals, and their latest disagreement has come over when exactly the FIA suggested a rethink of the upcoming engine changes.

Toto Wolff and Christian Horner target F1 engine rule changes

Fans who had long been wanting F1 to return to V10 engines were given hope following reports that FIA president Mohammed Ben Sulayem was pursuing the option, but they were dashed, for the time being at least, during the Bahrain Grand Prix weekend when senior figures – including Wolff and Horner – met to discuss the possibility.

With less than a year to go until major changes to Formula 1’s power units come into effect, it was agreed that the regulations would stay as they are and Wolff has now described the late proposal as a “joke”, suggesting it was “as hilarious as reading some of the comments that I see on Twitter on American politics.”

“Reading the agenda of the F1 commission is almost as hilarious as reading some of the comments that I see on Twitter on American politics,” he told media, including PlanetF1.com, at the most recent race in Saudi Arabia.

“I really want to protect ourselves and make no comment, but it’s a joke. Like a week ago, there’s an engine meeting and then things like this end up on the agenda again.”

The FIA released the 2026 Formula 1 power unit regulations on August 16, 2022, and the movement toward sustainable fuels and bigger reliance on battery power attracted the likes of Ford, Audi and General Motors to become interested in the sport, while Honda reversed their decision to leave.

Therefore, any change to 2026 regulations was always unlikely, but Horner countered Wolff’s comments, suggesting this had been on the agenda for a number of years and not something Red Bull pushed for.

“They [Mercedes] seem very confident in the job that they’ve done for next year,” Horner, whose Red Bull Powertrains division will create their first engine without the help of Honda next year, said. “I think that this is something that we asked to be looked at two years ago, and it’s not something that we pushed to be on the agenda this week at all.

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“The FIA have gone away and done their research, and I think what they want to desperately avoid is a lot of lifting and coasting in the grand prix itself, which will be not particularly good for the sport and hugely frustrating for the drivers.

“So it’s not something that we’ve lobbied for or asked for and if they’re doing it in the interest of the sport, then you’ve got to support it.”

Horner was pressed on the lift and coast concern and said this should have been looked at years ago.

“The problem is, the faster cars go through the corner, the bigger the issue will be and the designers will always design cars that go quicker through the corners,” he said.  “The FIA think they will so then that only compounds your problem.

“I actually think what they’ve proposed – that you have a push to pass element in the race to deploy – actually looks pretty sensible, but it’s something that obviously we should have ideally looked at two years ago but it’s still 10 months before we’re racing. So I don’t see it as a major issue.”

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