Ground staff at British airport operator BAA have voted to strike in a dispute over pay, the union Unite said, a move which could shut many of the country's busiest airports.
Unite said its members at BAA, owned by Spanish group Ferrovial, had voted three-to-one in favour of industrial action.
The union said its officials would meet on Monday to decide dates for any walk-outs. The union has to give seven days notice of any action.
More than 6,000 employees were balloted, including security guards, firemen and engineers essential to keep an airport running.
The union said 3,054 of those balloted had taken part in the vote, with 2,263 voting in favour and 791 against.
Regulations require minimum levels of staffing for airport fire stations and security gates, meaning BAA airports, which include London's Heathrow and Stansted, risk being closed by the strike action.
The union said staff had already accepted a pay freeze in 2009 and that this year the company had offered staff a 1% rise, plus 0.5% which was conditional on changes to a sickness agreement.
Unite also wants workers to receive a performance-related bonus which it said was promised to them if the company hit a certain financial target.
