The move is a reaction to unexpected gains in the level of performance the 2023 F1 cars are delivering. 

Why are Mercedes going backwards in F1 2023?

Across the opening five races of the season, F1 has seen a consistent leap forward in lap times. Sergio Perez’s pole position at last weekend’s Miami Grand Prix was almost two seconds faster than last year. 

That is despite changes to the floor regulations being introduced over the winter that were expected to cost around half a second.

F1’s rules state that the range of compounds used during a season must be determined by December 15th the previous year, however, changes can be made with the FIA’s approval. 

Governing body the FIA has given Pirelli permission to introduce a new specification of tyre that will be capable of dealing with the higher than expected loads. 

The new tyres will be made available for teams to test for the first time during practice at the Spanish Grand Prix in June, before being introduced at Silverstone the following month. 

“We’ve seen how much more performance the 2023 cars have compared to last year throughout the opening races of this season, and that is thanks to the extraordinary pace of development shown by all 10 of the teams,” Pirelli's head of motorsport Mario Isola said. 

“In Miami, for example, the pole time was nearly two seconds faster than last year, but the same sort of progress has been seen during races as well.

“Pirelli’s simulation work has always been aimed at not only supplying a product that hits the performance targets specified by stakeholders, but also anticipating any potential problems and reacting to them quickly.

“The new specification contains materials that we have already developed for 2024, which will make the tyres more resistant without affecting any of the other technical parameters or their behaviour on track. 

“To allow all the teams to test the new construction on a level playing field, Pirelli will supply two extra tire sets per car to be used during FP1 and FP2 at the Spanish Grand Prix.”