Ryanair said on Tuesday the strike at Boeing’s US aircraft assembly plants was forcing it to postpone the opening of its new operating base at Edinburgh, Scotland because of the delay in the delivery of new aircraft.

Europe’s leading low-cost carrier, which is one of Boeing’s biggest customers for short-haul jets, said the delivery of two 787-800s had been “indefinitely delayed” by the strike that began at the weekend and has closed Boeing’s US aircraft assembly.