WARSAW (Reuters) - 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 Boeing 737-800 aircraft taxi at Manchester Airport, Britain, January 8, 2018. REUTERS/Phil Noble

Ryanair is currently a market leader in Poland with around 30 percent share. Its biggest rivals include Polish state carrier LOT [LOT.UL] operating from Warsaw’s main Chopin airport.

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

“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.

The Polish state-owned airport company PPL has a 30.4 percent share in Modlin, which is about 40 km 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, about 100 km from Warsaw.

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

State carrier LOT has backed the plans for a new airport, which it sees as the pillar of its ambitious international expansion strategy. The plans envisage moving all passenger traffic from Chopin to the new hub.

Meanwhile, PPL told state news agency PAP that it disagreed with Ryanair’s argument and had filed its own complaint to Polish competition authorities, saying Ryanair is abusing its position as the only airline operating from Modlin.

“In our assessment when it comes to the airport in Modlin, the source of the problem lies elsewhere -- no airline wants to land at an airport dominated by a single carrier,” PPL told PAP.

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

Some experts have said the new airport would struggle to become profitable and fill its capacity.