Thousands of London bus workers have voted to go on strike in a row over extra pay for working during the Olympic Games.

Members of the Unite union backed industrial action by more than nine to one, raising the prospect of crippling walkouts during the Games, which start in the capital next month.

The union is seeking a payment of £500 for each of the 20,000 bus workers it represents in London, pointing out that other transport employees are being paid a premium for being on duty during the event.

The union will decide in the coming days whether to name strike dates following the ballot result.