The Irish carrier announced in December that it would finally recognise pilots’ unions for collective bargaining purposes after resisting this move for years.

Balpa will be the “sole representative” for Ryanair’s UK pilots, who have already voted to accept pay increases of up to 20%. The UK currently accounts for around 25% of Ryanair’s fleet and pilots.

Eddie Wilson, chief people officer at Ryanair, said: “This agreement validates the decision of Ryanair’s board in December to recognise unions, and the fact that we have delivered pay rises of up to 20% and union recognition for our pilots in our largest market, shows how serious Ryanair is about working constructively with unions that are willing to work constructively with us.”

But Ryanair has criticised unions in other countries, including Ireland, for not signing up for similar agreements with the airline.

“This rapid progress in the UK is in marked contrast to some other EU countries where we are still waiting for a response to our recognition proposals and where some unions have failed to put these substantial pay increases to our pilots,” said Wilson.

Brian Strutton, general Secretary of Balpa, added: “Given Ryanair’s previous hostility towards unions, today’s agreement is an historic one.

“While we were initially sceptical about Ryanair’s sincerity in offering recognition to us and other unions, our conversations and meetings with them have shown that they are genuine in wanting a constructive trade union relationship.

“Our discussions in getting to a recognition agreement have been tough and required compromise on both sides.”