Ferrari's Fernando Alonso has gone quickest in the second free practice session at the Valencia Street Circuit, using the PZero Yellow soft tyres. The two-time world champion's lap of 1:37.968 comfortably eclipsed the FP2 benchmark last year of 1:39.283, also set by the Spaniard.

The PZero White medium rubber made its debut as a nominated tyre during a race weekend, having been tested by the teams during free practice in Canada. Red Bull Racing's Mark Webber was quickest in the first free practice session this morning, using the new PZero White to set a time of 1:40.403: again quicker than the equivalent session last year (1:41.175, Nico Rosberg).

The top four fastest drivers - Fernando Alonso, Lewis Hamilton, Sebastian Vettel and Michael Schumacher - were covered by just four-tenths of a second and represented four different teams, highlighting the performance and versatility of the PZero tyres on a wide variety of different machinery.

Weather conditions were overcast throughout the day, with an ambient temperature of 27 degrees centigrade and a maximum track temperature of 38 degrees. When the cars took to the track for the first time there was extremely little grip, with plenty of dust and debris thrown up before the surface began to rubber in during the afternoon.

This resulted in the track getting progressively faster, with Alonso's time in the afternoon only half a second off last year's pole time. The difference in time between FP1 and the pole time in 2010 was 3.588s; one of the biggest differences of the year and a sure sign of how quickly this circuit can evolve. The weather forecast for the rest of the weekend indicates that conditions will clear up, with hot temperatures predicted for Saturday and Sunday.

Paul Hembery: "It's been a very encouraging start here for the new PZero White medium tyre and the PZero Yellow soft tyre, both in terms of performance and durability. This is the most abrasive street circuit that we will face all year, but we're still expecting only one or two stops for the majority of competitors and a difference of about a second to a second and half per lap between the medium and soft tyres. With the new medium tyre, we should see a range of about 30 laps on race day and about 20 laps for the soft tyre, putting us on course to meet our targets for this event."

To check out our Valencia practice gallery, click here.