Team bosses have joined the growing chorus of criticism of the proposed 2026 rules overhaul.

The outline of the regulations revealed, without warning, by the FIA on Wednesday, was greeted with scepticism by the drivers, who expressed concern at a number of issues including weight and speed.

While Fernando Alonso admitted concern that the new generation of cars will be "too slow", George Russell is worried they will be too high, and dangerous on superfast circuits like Monza and Jeddah.

However, their criticism is shared by the team bosses, leading to speculation over just how involved they have been in the whole process.

James Vowles agrees with Alonso's claim that the power units will continue to impact weight which will in turn impact speed.

"I think there's probably two different carves out of concerns at the moment," said the Williams boss. "First and foremost, there's the aerodynamic side, so what we're doing with either freedom or physically how fast the cars will be. And then the second side of it is where we are on weight.

"And I've been vocal already a few weekends ago that I put it from William's perspective, but I don't think anyone will hit that weight target particularly," he added. "It's going to be incredibly difficult, and I think that needs reviewing because there's someone that spends their life going through marginal gains taking weight out of a car.

"On the second side of things, I would absolutely agree that if we work together, and we will do going forward on this one, we can get it to a really good position, I think. It's a solid foundation to work from, but we do need to clear up some aspects of it."

Vowles insisted that it is "imperative that we are still the leading series in motorsport". "The performance difference to an F2 car could be as small as a few seconds," he added, "and that's starting to get a little bit tight, especially when you compare it to the other series around the world."

"We are in agreement and we support the intent and the objectives at eye level that were stated in the press release," said Andrea Stella. "However, if we look at the regulations in the draft form that has been circulated, they are still far from being able to achieve those agreeable objectives and intent.

"So it is the time for the FIA, F1, and the teams to work together, listen to one another, and contribute to form a solution that will allow the sport to meet those objectives," he added. "I think if we meet those objectives, we're going to have Formula 1 in good shape. But we need to make sure that when it's the time of implementation, we actually deliver a product that meets those targets and objectives."

The Italian is particularly concerned that the increased electrical output from the new power units will put too much demand on the aero and chassis in order to compensate.

"I think the main gaps are in Article 3, which is the aerodynamic regulations," he said. "And the second one is I still think that the way in which the power units are planned to be used needs to be adjusted.

"We can still achieve a 50-50 concept, which is a nice concept," he admitted, "but it can be achieved in a way that doesn't put so much of a requirement on the chassis side, which is difficult to meet.

"So I think from a power unit point of view, likewise from a chassis point of view, it's time that all parties understand that they need to contribute to the success of the sport."

In terms of the active aero, which features a 'Z-mode' that generates more downforce in corners and an 'X-mode' which increase top-end straight-line, Stella agrees with both Russell and Alonso

"The cars are not fast enough in the corners and too fast in the straights," he said. "So these two aspects need to be rebalanced."

Mike Krack was keen to make clear that the rules issues by the FIA are not set in stone and need to be refined, preferably behind closed doors.

"I think we are quite far away still from the final one, and I think it's now up to all stakeholders to discuss, to work on possible issues constructively rather than using the media to try and put something forward," he said. "So I think over the next weeks and months on TAC level, I think we will be able to iron out all the issues that are still there."

Meanwhile, reflecting on the complexity of the new rules, the Aston Martin boss fears new fans will be left cold.

"It's a lot of engineering language," he said. "It's like 'Z mode', 'X mode', energy management and so on. In terms of complexity, I think we need to focus on the product and the fan, and the spectator.

"I'm a bit scared that in 2026, we will have driver press conferences or driver interviews speaking about all these technicalities and a lot of people will not understand and lose interest just because of that. So that is something that I think we need to be really careful."

Meanwhile, at Haas, Ayao Komatsu is concerned at the increasing lack of freedom in design, with the proposed regulations taking it a step further.

"At the moment in the draft regulations, I'm not sure if that balance is hit right in terms of how things are prescribed," he said. "F1 is one of few remaining forms of motor sport where teams are required to design and build their own cars.

"All those philosophies, how we present ourselves as the pinnacle of motorsports, in terms of engineering as well, to have some freedom or probably a bit more increased freedom in aerodynamics, that is important as well. So again, there's various aspects we need to look into to make it really represent the pinnacle of motorsport."

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