A decision on the future of air passenger duty on the Belfast to New York route will be taken "well before Christmas", the economic secretary to the Treasury has told MPs.
Justine Greening said a resolution would be in "the best interests of the whole of the UK", but she would not be drawn on when the final outcome would be made.
Ms Greening was giving evidence to the Northern Ireland Affairs Committee on 29 June 2011.
The committee is investigating whether the air passenger tax - which adds £60 on flights from Belfast to New York - should be scrapped.
Earlier this month Continental Airlines said it may be forced to withdraw its Belfast to New York route because of the tax.
Conor McAuliffe, managing director of Continental Airlines, told the committee that the air passenger duty is a "regressive tax" that is "bad for the UK economy".
Mr McAuliffe pointed out that a family of four flying to New York from Belfast would pay £240 in air duty, whereas if they went "down the road" to fly from Dublin they would only pay 12.
He said that his company's Belfast operation was making a loss and could not "continue indefinitely".
The route is estimated to be worth around £20m a year.
Chief executive of the Northern Ireland Hotels Federation, Janice Gault, told MPs that it would be a "Titanic-style disaster" if the Belfast to New York service were to stop operating.