One of Europe’s largest airlines, Virgin Atlantic, predicts the price of transatlantic flights will drop dramatically if Norwegian Air International's (NAI) is allowed to establish their Ireland-Boston flight routes.

Virgin Atlantic’s chief executive Craig Kreeger has revealed that the UK airline sees the introduction of NAI to the transatlantic market as a serious threat to their own customer base.

“They’re someone we compete with aggressively,” Kreeger said.

“We need to – and we do – take them very seriously.”

After a two year debate, the US Department of Transport (DofT) made a tentative decision in April 2016 to grant a foreign carrier permit to Irish-based airline Norwegian Air International, a subsidiary of low-fares giant Norwegian Air.

The airline aims to begin a Cork to Boston route this year, extending to a Cork-New York route in 2017.

This DoT decision was one two years in the making, however, as the Norwegian airline's plans have been met with criticism in the US from unions and politicians who feel that they company is taking advantage of Ireland's lax labor laws in order to avoid worker’s rights responsibilities.

By basing a subsidiary of the company in the Republic of Ireland, the Norwegian airline had hoped to take advantage of the Open Skies Agreement, which allows EU-registered airlines to fly to the US from anywhere in Europe.

The airline has been accused of planning to outsource employment to Asian countries, an accusation executives have firmly denied, in turn accusing their opponents of creating a “wildly inaccurate fear-mongering situation.”

Read more: Sanders slams planned Cork-Boston airline flights as anti-union

US authorities were criticized this week for the delay in granting the permit by the European Commission’s transport chief, Henrik Hololei. NAI had hoped to launch their Irish flights last April but have been forced to postpone.

Virigin is already struggling to compete with UK rivals British Airways, and now Virgin is keeping a close eye on the Norwegian airline as they expand their fleet from 10 to 42 by 2020.

Despite the backlash in the US, the introduction of NAI transatlantic flights is widely welcomed in Ireland with nine out of ten people supporting the route.