Hamilton handed French GP grid penalty.

Both Lewis Hamilton and Nico Rosberg will have to begin the French Grand Prix in a fortnight's time ten places lower on the starting grid, dealing a hefty blow to the former's world championship chances.

The drivers were deemed culpable of having caused an avoidable accident in Montreal, after Hamilton piled into the back of chief title rival Kimi Raikkonen in the pit-lane during the Canadian Grand Prix, with Rosberg hitting the back of the McLaren-Mercedes just seconds afterwards.

Raikkonen and eventual winner Robert Kubica had both jumped earlier runaway leader Hamilton during the first round of stops on lap 19, but while they both waited at the end of the pit-lane for the red light to turn green, the Briton - seemingly unaware that the red light was on at all - arrived too fast and, despite taking avoiding action, hit the back of the Ferrari, with Rosberg following suit behind.

Hamilton and Raikkonen were out on the spot, with Rosberg touring around for a new front end on his Williams before going on to finish the race outside the points in tenth.

Now both have seen their hopes of scoring in what looks set to be the last French Grand Prix for the time being damaged by the penalties, especially given Magny-Cours' reputation for being a particularly difficult track on which to overtake. Whatever happens, Hamilton will now begin the race no higher than eleventh.

Leaving Montreal, the Briton has slipped behind Kubica in the title standings, sitting four markers adrift of his Polish rival with eleven races left to run.

Hamilton was previously threatened with a ten-place grid penalty for last year's Chinese Grand Prix in Shanghai - at a pivotal time for his championship challenge - following the incident that removed both Mark Webber and Sebastian Vettel from the rain-lashed Japanese Grand Prix at Fuji just a week earlier.