Ryanair boss Michael O'Leary warned on Thursday that the Russian war in Ukraine would cause travel disruption for European airlines for years to come, a day after Poland shot down suspected Russian drones in its airspace. Several Polish airports were temporarily closed on Wednesday as the country shot down Russian drones, before flights resumed hours later. "This is going to be an ongoing issue for all airlines and all European citizens for the next number of years," group CEO O'Leary said. O'Leary said safety was Ryanair's priority, adding that he was confident European authorities would act swiftly to shut airspace and protect aircraft. Shares in Ryanair were up 2.4% by 1248 GMT, recovering ground from Wednesday when the Polish incident sent most European travel stocks lower.