Major airlines would be hit by the strike

About 1,000 members of the Transport and General Workers Union (TGWU) will begin a 48-hour strike on Sunday in a row over pay.

They claim they have not been given an increase in salary for 18 months.

The members, who are employed by two companies run by Swissport, work as baggage handlers and check-in staff for 21 airlines, including Aer Lingus, El Al and Malaysian.

Union officials claim Swissport walked out of talks on Wednesday after almost four hours.

In a ballot more than nine out of 10 workers backed taking industrial action.

A spokesman for Heathrow said the airport would be ensuring on Thursday that contingency plans are in place for the weekend.

Singapore Airlines, which was thought to be affected, say it uses a separate company and passengers will not experience disruption.