Irish low-cost airline Ryanair said it had filed a complaint to European competition authorities over a Polish airport company’s alleged refusal to expand Warsaw’s Modlin airport which Ryanair uses as its Polish base.

“Ryanair has confirmed that over the next five years it will double the number of passengers on its flights to Warsaw from 3m to 6m annually,” the company said in a statement on January 19.

“To service such a level of traffic, the infrastructure of the Warsaw Modlin airport needs to be expanded, which for nearly two years has been unlawfully blocked by the Warsaw Chopin airport,” Ryanair said.

As reported by the Reuters news agency, Ryanair is currently a market leader in Poland with around 30% share. Its biggest rivals include Polish state carrier LOT operating from Warsaw’s main Chopin airport.

The Polish state-owned airport company PPL has a 30.4% share in Modlin, which is about 40km from Warsaw. PPL is also the sole owner of the Chopin airport, which is located within the city borders.

Plans to expand Modlin — a small airport which gets very crowded — have slowed down after the government’s recommendation to build a large new airport in central Poland, according to Reuters.

Experts have said that opening a new hub airport would likely lead to the closure of several airports in central Poland.

Ryanair has opposed plans for the new airport, with Chief Executive Michael O‘Leary calling the idea “stupid” and “a waste of money”.