Lewis Hamilton believes the collision with Mercedes rival Nico Rosberg in yesterday's Belgian Grand Prix has made it very tough to overtake the German in the Formula One drivers' championship.

He said: "I don't know why he hit me but I'm sure he'll leave here happy."

The second-lap collision ultimately forced Hamilton to retire on lap 39 while Rosberg finished second behind Red Bull's Daniel Ricciardo to extend his championship lead over the Briton to 29 points.

The German was jeered on the podium at the end of the race.

A disconsolate Hamilton said: "It's really gutting. I was trying so hard in the car to do what I could with it but it was so damaged, I must have lost 50-60 points of downforce.

"I'm gutted for the team. We've had such a difficult time this year. We had a good start, it was looking positive."