A series of fresh strikes by security guards at Heathrow Airport in a dispute over pay has been announced.
The Unite union said more than 2,000 of its members will walk out for 31 days from June 24.
For the first time security officers based at Terminal 3 will join their colleagues from Terminal 5 and campus security who have already taken industrial action.
Unite general secretary Sharon Graham said: "Unite is putting Heathrow on notice that strike action at the airport will continue until it makes a fair pay offer to its workers.
"Make no mistake, our members will receive the union's unflinching support in this dispute.
"Heathrow Airport has got its priorities all wrong.
"This is an incredibly wealthy company, which this summer is anticipating bumper profits and an executive pay bonanza.
"It's also expected to pay out huge dividends to shareholders, yet its workers can barely make ends meet and are paid far less than workers at other airports."
The workers will be on strike on June 24, 25, 28, 29 and 30, and July 14-16, 21-24, 28-31 and August 4-7, 11-14, 18-20 and 24-27.
The strikes will coincide with the beginning of the school holidays and the August bank holiday.
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