Paris, France (AFP) — Formula One chiefs unanimously agreed on Monday to make rule changes following severe criticism of new regulations introduced this season, which led to doubts over Max Verstappen continuing in the sport.

The new rules made cars a combination of combustion and electrical power, meaning drivers had to carefully manage their battery, effectively slowing down on a qualifying lap, while the cars had boost buttons to allow them to overtake.

Four-time world champion Verstappen called the new style of racing “a joke” after the Chinese Grand Prix and hinted he would take a break from F1 in 2027 unless changes were made.

Other drivers had criticised the new rules and fans said the changes had detracted from the experience of spectators.

Following an online meeting between F1, its governing body FIA, and the sport’s team principals, tweaks to the rules have been finalised and are set to come in for the Miami Grand Prix on 3 May.

That race will end the season’s enforced five-week break following the cancellation of the Bahrain and Saudi Arabia races due to the conflict in the Middle East.

Among the changes, energy harvesting — which helps the driver charge the battery -- will be reduced from eight megajoules to seven and the hybrid power unit will be increased from 250kw to 350kw.

The changes are designed to allow the drivers to go at full speed for longer in qualifying.

Another change has been made to the boost button, after British driver Ollie Bearman’s high-speed crash at the last round in Japan, which was attributed partly to the difference in closing speeds.

The boost button will now be capped at 150kw, “limiting sudden performance differentials,” the FIA said in a statement.

Further talks are set to take place after the Miami Grand Prix.

Mercedes team principal Toto Wolff cautioned against sweeping changes to the rulebook, after his drivers Kimi Antonelli and George Russell made a fast start to the season. Antonelli leads Russell by nine points in the standings after the first three races.

Speaking before the meeting, Wolff said: “The discussions that have been taking place between the drivers, the FIA, Formula One, and the teams have been constructive. And we all share the same objectives.”

“It’s how we can improve the product, make it out-and-out racing, and look at what can improve in terms of safety, but act with a scalpel and not with a baseball bat.

“We are going to ratify, in order to evolve, because there has only been three races. We need to learn from the past, where decisions were sometimes made in an erratic way, and then we overshot and realised it wasn’t good.

“We are custodians of the sport and we have many hundreds of thousands of fans who love F1. In order to protect this huge opportunity that the sport gives us, we shouldn’t badmouth in public our own sport.”