Flybe has axed several flights from Belfast City Airport this summer and announced it is operating a reduced schedule for others.
The airline blamed "late aircraft deliveries".
The company only recently announced new routes from the airport for summer 2022 but it seems these will now have to be cancelled.
There are reports the routes may be delayed until 2023.
Flights operating at a reduced frequency include:
Belfast City to Birmingham, Edinburgh, Glasgow, Manchester and Southampton
Birmingham to Edinburgh and Glasgow
Meanwhile, the following routes have been cancelled:
Belfast City to Aberdeen, Inverness and Newcastle
Birmingham to Aberdeen
In an online statement, the company's chief executive said it will impact flights scheduled from 28 July to 29 October 2022.
Dave Pflieger said: "This is not a decision we have taken lightly, and as you would expect we are in daily conversations with all involved to see if anything might change that would allow us to resume our original plans at an earlier date.
"It is essential that we take action now to ensure you have enough time to change your travel plans, be re-accommodated on a different flight or, if that is not desired, obtain a full refund."
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