Ryanair boss Michael O'Leary has told the airline's staff to prepare for job losses as the company needs 900 fewer pilots and cabin crew than was previously thought.
In a video message to staff, reported by Bloomberg, Mr O'Leary claimed that Ryanair has 500 extra pilots and 400 more flight attendants than it needs.
On top of this the airline will need 600 fewer members of staff next summer than originally thought.
A spokesman for Ryanair confirmed the video was real but declined to comment.
Mr O'Leary said: "We will need about 600 less pilots and cabin crew for summer 2020.
"On top of this bad news, we already have a surplus of 500 pilots and some 400 cabin crew because resignations have dried up to effectively zero since the start of 2019.
"Added to these challenges in the last number of weeks is the increasing likelihood of a no-deal Brexit in just 12 weeks' time.
"We're worried this could have a very damaging effect, particularly on our 海角视频 bases and on some of our Irish bases, which are heavily dependent on people travelling between Ireland and the 海角视频.
Most Read
"I'm sorry to advise you that this means that we have to cut our aircraft numbers and our staffing, not just for summer 2020, but also in winter 2019.
"This will result in some base cuts, some base closures, and I'm very sorry to say, some job losses this winter for pilots and cabin crew.
"Over the next couple of weeks we will be doing our very best to minimise job losses, but some are simply unavoidable at this time."
Ryanair has suffered after delays of orders to receive a new fleet of aircraft from Boeing.
All Boeing 737 MAX planes were grounded this year after two fatal crashes took place in Ethiopia and off the coast of Indonesia. The crisis also led to Ryanair's delivery of a fleet of Boeing's MAX 200 planes to be delayed.
The budget airline has already warned that it will close site in the 海角视频 because of the problem, although until now the scale of the cuts was unknown.
Ryanair operates from 19 airports in the 海角视频. These are Aberdeen, Belfast International, Birmingham, Bournemouth, Bristol, Cardiff, Derry, East Midlands, Edinburgh, Glasgow, Leeds Bradford, Liverpool, London Gatwick, London Luton, London Stansted, Manchester, Newcastle and Newquay Cornwall.