Aer Lingus Regional franchise holder Emerald Airlines will boost services from Belfast City Airport following the failure of Flybe.
The British airline ceased trading at the weekend, less than a year since its rescue, partly blaming delayed aircraft deliveries for the move.
Emerald Airlines pledged on Monday to immediately add an extra 15,000 seats to services from Belfast City Airport, where it is already the biggest operator.
Belfast was one of the airports hit by Flybe’s failure, as the Birmingham-based airline offered several services linking the city with Britain.
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Emerald, which began operating Aer Lingus Regional last March, also said it would hold open interviews in Belfast’s Maldron Hotel on Thursday and Friday for workers hit by Flybe’s closure.
Conor McCarthy, the Irish airline’s executive chairman, said it was working on a comprehensive plan to ensure travel continued from Belfast City.
“Emerald Airlines is stepping up, safeguarding connectivity between Britain and Northern Ireland, as we have done for the last 12 months,” he added.
The carrier will add seats to services from Belfast to Birmingham, Edinburgh, Glasgow, Manchester and other British destinations.