Christian Horner makes 'embarrassing' Mercedes comment as ball put in Toto Wolff's court

The Mercedes and Red Bull rivalry continues to rumble on after Christian Horner suggested it would be 'embarrassing' for Toto Wolff's squad to produce inferior power units for the 2026 technical regulations. On Friday at the British Grand Prix, Horner described the 2026 technical shake-up as "the biggest rule change in Formula One probably in the last 50 years, with both chassis and power unit [changes] being introduced at the same time."

This also makes it a big opportunity for teams to gain on their rivals and put themselves at the top of the pecking order. For Red Bull, this regulation shift represents a bigger challenge than for most. Having previously enjoyed support from Honda, Horner's outfit will go it alone, producing their own power units via the Red Bull Powertrains branch of their Milton Keynes operations.

The team principal is already tempering expectations. "We understand the pressure that there is next year, with us coming in as a new power unit manufacturer," Horner said at Silverstone. "The challenge of that is enormous. But we've got a hugely capable group of people. We've invested significantly. We've got a great culture within the team. Who knows?

"To expect us to be ahead of Mercedes next year is... It would be embarrassing for Mercedes if we were, or for any manufacturer. But I think we're going to be in a competitive position, potentially even to where we are today relative to our other PU manufacturers. There's everything to play for."

Horner's scepticism is understandable. Mercedes boss Wolff echoed the 51-year-old's concerns about the Red Bull engine programme when approached about the topic at the Red Bull Ring.

"It's always possible that something good will come out of their new infrastructure and their people," he said. "But if you calculate how likely that is, it would be a real feat if they succeed in making a big splash right away."

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As for Mercedes, Wolff was giving nothing away. While Aston Martin will be supplied by Honda in 2026 as part of an exclusive agreement, the Silver Arrows will provide power units for returning customers Williams and McLaren, as well as Alpine, who have ditched their own programme.

"We're completely in the dark," he explained. "Perhaps there's some concept we've overlooked, both in the car and the engine. The main differences will be in the batteries, but in any case, we've already stopped putting much energy into the current car."

Currently, 47 points separate Mercedes and Red Bull in the Constructors' Championship. This is largely due to the struggles of Horner's second car, as reigning world champion Max Verstappen has scored all but seven of the team's 162 points in 2025.