Dozens of flights were grounded and thousands of journeys disrupted after British Airways pilots staged their first-ever strike, a two-day stoppage, on Monday and Tuesday, with a third day currently planned for Sept 27.

(File photo: AP)

Despite agreeing deals with other staff such as cabin crew and ground staff, nine months of pay talks between the airline and the British Airline Pilots Association (known as BALPA) have failed to make any progress, leading to what is expected to be the biggest walkout in the airline's history.

"We want to resolve this dispute as quickly as possible for our customers and, frankly, for everyone that works at British Airways," the airline's Chief Executive Alex Cruz told Sky News, adding that the action was "cynical" and an "own goal" by the unions.

In a statement on its website, BA said it "had no option but to cancel nearly 100 percent our flights" because BALPA could not say which members would be striking, making it impossible for them to estimate how many suitably trained staff would be available.

Passengers with flights booked for Monday or Tuesday were asked not to go to the airport, and further knock-on disruption is likely on Wednesday as well.

Details of refund or rearrangement procedures are available on the BA website, while passengers who booked through travel agents are advised to go to them for advice.

BA offered its pilots a three-year deal worth 11.5 percent, at the end of which the airline said the average captain would be earning more than 200,000 pounds ($246,000) per year.

Currently, long-haul pilots earn 167,000 pounds, with shorter haul flight crew on significantly less, but the pilots' union rejected the offer, saying it did not match the company's healthy financial results.

Speaking ahead of the strike, BALPA general secretary Brian Strutton said his side would "take stock" after the stoppage, and then consider its next action.

"We hope to see BA at the negotiating table but if it doesn't happen then we'll have to consider next steps, and as part of that further strikes are not ruled out," he said, adding that the situation was "pretty dismal" as BA had "shut down" all dialogue.

The Financial Times reported that, ahead of the strike, BA had sent an email to its 4300 pilots warning them that perks such as significantly discounted tickets for them and their families could be withdrawn for up to three years, and any existing bookings would be cancelled, having previously used similar tactics in disputes with other staff .

"We make no apology for doing everything we can to protect our customers from further disruption," said a company spokesperson.