Flights from Belfast City to Aberdeen, Inverness and Newcastle plus Birmingham to Aberdeen will be cancelled altogether.

There will also be reduced frequencies on services from Belfast City to Birmingham, Edinburgh, Glasgow, Manchester and Southampton, and from Birmingham to Edinburgh and Glasgow.

The airline’s chief executive Dave Pflieger said in a statement schedules would be affected from 28 July until the end of the summer season on 29 October.

In a letter to customers, he said: “We were planning to increase flights to existing cities and new destinations such as Aberdeen, Inverness, Newcastle, and Southampton. However, the two aircraft leasing companies who were contracted to provide our additional airplanes have now told us that they will be unable to fulfil their commitments until after the summer.”

He explained: “We were able to find and rent aircraft from two separate airlines in Greece and Spain, but those planes are not enough, and the lack of additional aircraft needed for new flying means we need to adjust our future flight schedule.

“As a result, today we are reducing our planned increase in flying for the period of 28 July until 29 October. This new schedule will be fully supported by the aircraft we do have available, and we will still introduce more flights later this year after we receive our delayed aircraft.”

Flybe has added a website channel to deal with flight changes and refund requests.