This article is more than 1 year old

This article is more than 1 year old

Air passengers flying from Heathrow on Monday and Tuesday next week have been warned to expect delays and disruption after talks between the airport and trade unions aimed at avoiding strikes broke down.

Heathrow warned of longer security queues on 5 and 6 August after a ballot of Unite trade union members pointed to an “overwhelming” rejection of the airport’s latest pay offer to security guards, firefighters, engineers and passenger service staff.

Passengers have been advised to call their airline and check online for details about when to arrive at the airport, although Heathrow said contingency plans would minimise the impact on passengers.

Unite warned that two more strikes could follow on 23 and 24 August, while a separate dispute between British Airways and its pilots is threatening to cause further disruption later this month.

A Heathrow spokesperson said: “We are disappointed that Unite has rejected the latest pay offer and will continue to seek an agreement at [conciliation service] Acas.

“Unite is proceeding with its unnecessary strike action […] and we regret that passengers looking to get away on well-earned breaks will be impacted by this.”

Unite urged Heathrow to “give hardworking staff a pay rise” to avoid 88,000 passengers being affected by the walkouts.

The union said Heathrow’s latest pay offer amounted to just £3.75 more per day than its first offer and warned the airport could end up having to pay £4.6m in compensation costs to airlines if two further strikes take place later in August.

“Our low paid members will sacrifice a day’s pay if they go on strike and are only too aware of the disruption it will cause,” said Wayne King, a regional officer at Unite.

“However, they are at a point where they have had enough with being given crumbs while shareholders pocket billions in dividends and the chief executive enjoys a pay rise of over 100%.”

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The threat of strikes at Heathrow came as the chief executive of IAG, which owns British Airways, urged pilots threatening summer strikes to accept BA’s “generous” pay offer.

Willie Walsh, a former airline pilot and union negotiator turned airline boss, said he was not involved directly in pay negotiations but advised pilots to accept an 11.5% pay rise over three years.

“If I was on management’s side I wouldn’t have made such a generous offer and if I was on the union side I would have grabbed it,” he said.

Talks with the pilots’ union Balpa are continuing in an effort to stave off strikes that could begin this month if the union gives two weeks’ notice of a walkout.