The Government has pledged to work to restore flights connectivity following the collapse of operator Stobart Air.
Stobart Air informed Aer Lingus on Friday night it was terminating its franchise agreement and was in the process of appointing a liquidator.
The sudden announcement led to the cancellation of several flights on Saturday from Dublin and Belfast City airports to UK cities.
Aer Lingus said it had progressed alternative flying operations for regional customers which have taken effect from Sunday.
But alternative operations for flights from Dublin to Kerry and Donegal are still to be decided.
Foreign Affairs Minister Simon Coveney told: “I know that Aer Lingus’ regional service have taken over a number of Stobart routes, but only a number of them and that doesn’t include Kerry and Donegal yet.
“I can assure you that regional connectivity is important to this Government, we have been putting significant amounts of taxpayers’ money into subsidising the routes between Dublin and Kerry and Dublin and Donegal for good reason, to ensure that there is regional connectivity by air.
“That policy decision by Government hasn’t changed because of the really unfortunate circumstances around Stobart Air.
“There are no shortage of planes and operators right now.”
Sinn Fein TD Claire Kerrane told RTE’s The Week In Politics: “For the 480 people who lost their jobs immediately yesterday morning and for their families, they need support.
“The Government need to ensure that connectivity is restored as quickly as possible.
“The announcement yesterday will not be the last if Government do not take action. The Government need to act before more job losses are announced.”
Aer Lingus has said it will directly operate the Dublin to Edinburgh and Manchester routes, and the Belfast City flights to Manchester, Birmingham and Edinburgh following the collapse of Stobart Air.
BA City Flyer will operate the routes from Belfast City to Exeter and Leeds Bradford.
Customers scheduled to travel from Belfast City to East Midlands, and Dublin to Glasgow or Newquay routes are being offered alternative flights.