BRITISH Airways passengers face ruined summer holiday plans after pilots' union Balpa issued the airline with a formal notice of a strike ballot amid an ongoing pay dispute.

The Unite and GMB unions are expected to follow suit, with the three unions representing around 40,000 BA employees.

In a statement, Balpa said it had been in negotiation with BA, along with Unite and the GMB, since November 2018.

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Balpa says with BA posting record profits, its current pay offer is insufficient and “fails to address the fundamental principle of fairness by denying employees a reasonable share of the success they have helped produce”.

Last year BA made an operating profit of €1.95bn (£1.73bn).

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It is the first time that unions representing pilots, cabin crew, ground staff and engineers have joined forces in negotiations.

The airline's most recent offer was made at the end of May.

The offer for pilots is worth 11.5% over three years, said BA, adding that it remains in talks with Unite and GMB.

Balpa launched an informal consultation on the proposal which, it says, resulted in 96 per cent of pilots calling for a strike ballot.

BALPA general secretary Brian Strutton said: “All three unions have been working for the benefit of their respective members. Given we collectively represent some 40,000 employees, this is something British Airways should pay careful attention to.

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“For the pilots Balpa represents, it is quite simple: BA has been enormously profitable, and the employees should have a fair share of that success which, after all, they produce for the company.”

A BA spokesman said: "We are extremely disappointed that Balpa has raised the prospect of a ballot for industrial action.

"We urge them to join us for mediation with the conciliation service Acas, to reach an agreement and protect hard-working families planning their summer breaks.

"We believe our pay and benefits for pilots are among the best in the industry, with around 1,000 applications from pilots who want to move to us from other airlines every year."

It comes a matter of days after Unite announced to further dates of industrial action at Glasgow Airport for their industrial action in their pay claim dispute. The new dates for action are June 28 and 30.

The union is to consult members after a new pay offer was made by Aberdeen Airport’s managing committee but the two days of planned action are still scheduled to take place on June 27 and 28 June both commencing at 6am until 10am.

The action undertaken involving airport security officers, airport fire safety, airfield operations officers, and engineering technicians has resulted in long delays at airport security, and suspension of flights.