Two days of strikes by British Airways pilots next week look increasingly likely as the airline rejected an 11th-hour union call to resume pay talks.

The olive branch was offered yesterday by British Airline Pilots Association in a letter to BA chief executive Alex Cruz.

Pilots are due to walk out on Monday and Tuesday but the union put forward a new proposal in a bid to come to a deal with the airline.

The strikes, voted in favour by 93% of Balpa members working for BA, are set to go ahead with the airline revealing that the “inflated” union proposal would cost it an extra £50 million.

Unconfirmed reports this morning suggested almost 1,600 flights were at risk of being grounded with more than 250,000 passengers affected as up to 90% of BA’s 4,300 pilots are expected to walk out.

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The offer so close to the strike dates was seen as too late avert flight disruption with contingency planning having reached a “critical stage,” according to BA.

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Pilots union denies BA claim of talks to resolve pay row

Balpa general secretary Brian Strutton said: “Our members’ resolve is very strong and they remain very angry with BA, but they also want to leave no stone unturned in trying to find a resolution to their dispute.

“Avoiding strike action and agreeing a deal with their pilots surely must be the desired outcome for British Airways.

“We urge BA to join us to discuss the new proposal – which shows pilots are willing to be flexible but still stand united in getting a better deal.”

BA said: “We remain open to constructive talks with Balpa to resolve the pay negotiations, but we do not believe the union is acting in good faith by making an 11th hour inflated proposal which would cost an additional £50 million.

“We, at BA, have acted with integrity through many months of negotiations. We and the union’s leaders agreed and shook on a deal on Monday 12 August only for the union to back track on that agreement and return with new and unrealistic demands.

“Balpa has cynically waited until we have helped the vast majority of customers with alternative travel arrangements, and our planning for a strike has reached a critical stage. Our customers need the certainty that Balpa will call off the strikes for good, not just for two days next week.

“Ninety per cent of our staff are already receiving the 11.5% pay deal in their salaries, we urge Balpa to return to negotiations without pre-conditions, so that their members can do the same.”

“We continue to be available for constructive talks, on the basis that there are no pre-conditions to those talks.”

Adam French, consumer rights expert at Which?, said: “After the chaos caused by British Airways’ email errors, it is vital the airline now does everything possible to minimise disruption and ensure all passengers are kept up to date on how this will affect their travel plans.

“It must do right by its passengers and ensure that anyone whose flight is cancelled is rerouted – with a rival airline if necessary – or refunded.”