Christian Horner and Toto Wolff remain at odds as Red Bull boss calls for rethink on the 2026 engine regulations.

With the switch back to V10s appearing to have been nothing more than a carrot to appease long-standing fans, a long-time concern over next year's (engine) rules overhaul is the 50/50 split between ICE and electric power.

There have been calls for the split to be tweaked at certain tracks for fear that, in an effort to conserve energy, drivers will lift and coast.

When the matter was raised at the most recent meeting of the F1 Commission, Toto Wolff described the move to tweak the rules as a "joke".

However, ahead of its debut as a power unit manufacturer in its own right, Red Bull's Christian Horner still believes the matter needs to be reconsidered.

"Look the regulations are fixed for next year and that's what everybody's designed and developed their engines, and I think the biggest concern is one that's not a new concern," the Briton told reporters in Miami.

"It's one that's been flagged from two years ago from all of the PUMs," he continued, "that's the amount of harvesting that there is.

"Inevitably that the chassis designers will outperform the criteria of the regulations and therefore, a consequence of that will be the amount of lift and coast that there will be in a Grand Prix. What you have to remember with the '26 regs is that the car is effectively constantly in DRS mode so as soon as you enter the straights the wings open, so there will be no passing mechanism.

"The FIA have raised a topic that was looked at a little while ago by the PUMs," he added. "If it's something that's genuinely in the interest of the sport, in the interest of racing, not to have all this lift and coasting I think it's something that does warrant looking at and considering but it doesn't actually change the spec of the engine," he argued.

"It doesn't change the output of the engine, it's just the amount of deployment of the battery, maybe at certain Grands Prix."

When Mercedes first returned to the sport it was purely as a manufacturer, and Toto Wolff, aware that the smart money is on the Three Pointed Star doing the best job with the new regs, as in 2014, doesn't want any late tweaks.

"Obviously the closer you come to new regulations the more you know people act in - all of us - in the interest of the team," said the Austrian. "That's our duty and I guess where we come from is we don't know how it's going to pan out next year.

"Are we going to see energy harvesting disasters in Baku and Monza? I don't know," he admitted, "we hope not and what we have signalled is that rather than act now based on assumptions like we have been great at in previous years and then we've overshot or undershot.

"It's not like you need to throw the hardware away and then come back with something new.," he said. "It's within the software, it's within the bandwidth of what you can do and we will see the final product hitting the road and testing next year and certainly you know us as a power unit manufacturer we want this to be a great show, we want to win but we are aware that there needs to be variability and unpredictability and we enjoyed the years from 2014 onwards but you know over a prolonged period of time that's certainly not the best for sport."

The 2026 rules overhaul, which was confirmed in 2022, has never been popular, but Wolff points out that despite this it has attracted the likes of Audi, GM, Ford and even caused Honda to rethink and remain.

"I see myself trying to be very balanced between what is good for Mercedes, which as I said, I need to do, but on the other side, what is the right solution going forward and we need to avoid these swings," he explained.

"The FIA proposed this engine, nobody liked it. The 50 per cent electric back in the day was what road cars were going to. It was a reason to attract manufacturers like Audi and Porsche, so we did that.

"So it's difficult to change the goal posts, especially for the new ones," he insisted. "Honda re-committed and Audi committed, and including us they are not keen on changing those goal posts at that stage, but we need to be open-minded if necessary next year."

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