US Congressman, Peter DeFazio has written to the European Commission to state his objection to the proposed operation of flights between Cork and Boston by Norwegian Air.

The service has been embroiled in a trade dispute. US aviation unions and some in Europe claim Norwegian intends to use its Irish air carrier permit to employ low-paid crew, a claim consistently denied by the airline itself.

US authorities are yet to grant the airline permission to operate, the European Commission believes that it should be given permission to do so, it has referred the issue to arbitration to resolve the dispute.

Norwegian Air says that the claims that it will sidestep labour laws are wrong, and that staff will be employed under the laws of where the airline is based.

The Democratic challenger for the US Presidency, Bernie Sanders entered this debate in May when he wrote to the  US Department of Transportation claiming that granting the licence would violate labour rules, and that it would set a "dangerous precedent" that threatens thousands of jobs, from flight attendants to mechanics and pilots on both sides of the Atlantic.

At the time a spokesman for the airline said, "Some US politicians and unions are continuing to do everything they can to block the competition, preventing passengers' access to affordable airfares, and blocking the creation of new jobs and significant benefits to Ireland and the US.

"The fact remains that NAI is a recognised EU airline, with a Dublin headquarters, more than 35 aircraft registered in Ireland and a series of new routes from Ireland planned."

The company added that it offers "competitive wages and conditions" in all territories.

This service was due to be introduced in April of this year.