More durable tyres confirmed for Spain

The compound, trialled during practice in Istanbul, is more durable and so will increase the gap between the prime and the option tyres, offering the teams a wider variety of strategies for the races.

Pirelli said, however, that it is still expecting three stops to be the norm in Barcelona this weekend.

"We said from the start of the year that we would introduce evolutions of the tyres if we believed that they would benefit the sport and Barcelona marks the first occasion that we have done this," said Pirelli's Paul Hembery.

"The new tyre - which we have tested extensively - reduces degradation and improves tyre wear.

"It's not a huge step over the original hard tyre but it does mean that there is a bigger gap between the soft and the hard tyre, which will definitely make things even more interesting on race day and give teams the opportunity to use more creative strategies.

"In Barcelona, based on the data we have seen in testing, we're probably expecting around three pitstops per car. It takes a lot longer to enter and leave the pits in Barcelona than it did in Turkey, and this is another factor that will have a definite influence on strategy."