FILE PHOTO - A man walks past a Ryanair aeroplane at Stansted airport in London, Britain September 27, 2017. REUTERS/Clodagh Kilcoyne

DUBLIN (Reuters) - Ryanair RYA.I recently applied for a British air operating licence in a move it said on Tuesday may be required to keep its small domestic UK service operating in the event of a hard Brexit.

Flying rights are currently governed by EU-wide deals and because it is not part of the World Trade Organization, the aviation sector has no natural fallback arrangement to protect flights if there is no deal between Britain and the European Union.

Ryanair, Europe’s largest airline by passenger numbers, follows fellow budget airline Wizz Air in applying for a separate licence in Britain via a UK subsidiary.

“A subsidiary company Ryanair UK filed an application on Dec 21 last for an Air Operator’s Certificate (AOC) with the Civil Aviation Authority in the UK. This may be required for Ryanair’s three UK domestic routes in the event of a hard Brexit in March 2019,” the airline said in a statement.

Ryanair said last year that it planned to pivot its growth away from Britain over the next two years as it fears the lack of clarity over Brexit will cause major travel disruption and hit demand.

The Dublin-based airline’s three intra-UK routes only account for around 2 percent of its business.