Paul Ricard FP1: Hamilton heads Mercedes one-two

Hamilton, a point behind Ferrari's Sebastian Vettel after seven races, complained about his car's handling over the radio but still put in a best time of 1:32.231 seconds.

His Mercedes teammate Valtteri Bottas, also with a 'new' Mercedes engine in his car, was second fastest in 1:32.371 as France made its return to the F1 calendar for the first time since 2008.

The 90-minute session was red-flagged with a minute remaining when Ericsson lost control at the Beausset corner, spun and hit the barriers hard, with the Sauber car then catching fire.

The Swede worryingly remained in the car taking his time to wiggle out, with flames licking the airbox, before marshals arrived with an extinguisher and he clambered out from underneath the halo head-protection system.

Video images later showed extensive scorching to the rear of the car.

Daniel Ricciardo, winner of two races this season and still mulling his future options, was third fastest for Red Bull in 1:32.527.

Ferrari's Kimi Raikkonen was fourth on the timesheets with Vettel fifth nealry a second adrift of his title rival at the top of the timing screens.

Romain Grosjean, in the Haas, was the highest-placed French driver in sixth place and ahead of Red Bull's Max Verstappen. Frenchman Pierre Gasly was eighth for Honda-powered Toro Rosso.

There was further misery for Williams and McLaren, two of the sport's most successful teams who are going through difficult times, with their drivers filling four of the bottom five places.

Spain's double world champion Fernando Alonso, winner at the Le Mans 24 Hours with Toyota last weekend, came down to earth with a bump in 16th place with McLaren team mate Stoffel Vandoorne 19th.

Sunday's race will be Formula One's first at Le Castellet's Paul Ricard circuit since 1990.