A Ryanair flight from Malta coming into Stockholm Skavsta Airport on Wednesday evening was told that it could not land as the airport was closed, a move the Irish low-cost airline has declared “illegal”.

“Our flight was due to land within the established curfew. We had to divert, and this was not something that was very beneficial for our customers,” Ryanair’s Stephen McNamara told The Local newspaper on Thursday.

“This has not happened before. Not at one of our hubs, anyway. Our people are talking to the airport today to get to the bottom of the issue,” he said.

A Ryanair statement on Thursday described the closure of the runway at Stockholm Skavsta Airport, about 100 kilometres south of the city, as “illegal.”

“It was illegal because we were not outside the required time limits,” Mr McNamara told The Local.

Passengers on the Ryanair flight from Malta were diverted to Stockholm Arlanda Airport, where they were transferred by coach back to Skavsta.

“Thankfully, as we had extra aircraft capacity at Skavsta, our flights have been able to run as normal today (Thursday),” said Mr McNamara

He explained that once the reasons behind the incident are established, Ryanair will raise the issue of compensation for the extra costs incurred.

But Skavsta chief Dot Gade Kulovuori rejected the budget carrier’s claims. Though reluctant to comment in any detail on the incident, she referred The Local to a statement posted on the airport’s website on Thursday afternoon.

“This [Ryanair’s] statement is incorrect; the airport is operating in accordance with its service level requirements as agreed with its airline partners. We deeply regret any inconvenience caused to those passengers affected and we shall continue to work with Ryanair to ensure that passengers wishing to use Stockholm Skavsta Airport receive the best possible service; this is of utmost importance to us.”