CRANES on flagship London building sites will be powered down next month after drivers voted overwhelmingly to strike.

HTC Plant Limited operates cranes for Crossrail, the controversial Elephant and Castle redevelopment and Britain’s nuclear bomb factory at Aldermaston among other projects.

The firm has slapped workers with multiple pay freezes since 2008, meaning wages have declined in real terms.

Members of building union Ucatt voted 94 per cent in favour of strike action and 94.6 per cent in favour of action short of strike.

The company’s offer of a 3 per cent rise this year was rejected by drivers.

“HTC needs to understand that crane drivers believe that they deserve a decent pay rise and are prepared to fight to win one,” said Ucatt general secretary Steve Murphy. “The only people who can prevent construction chaos are HTC.”

The union said it had seen a membership surge at HTC sites since launching its strike ballot.