Ryanair is to vastly reduce flights from Glasgow Airport, making Edinburgh its main base in Scotland.
The Irish budget airline currently operates flights from both airports and Prestwick in Ayrshire but will have only three flights from Glasgow this winter.
Chief commercial officer David O’Brien said the decision was down to Air Passenger Duty.
A spokesman for Glasgow Airport said: “We are bitterly disappointed at this decision by Ryanair, which is not only damaging for Glasgow and wider Scottish connectivity, it will impact approximately 100 jobs locally.
“This is a result of the airline’s review of its single aircraft bases; however, we have been left in no doubt it is also a consequence of the Scottish Government’s inability to introduce its proposed 50% cut in Air Departure Tax (ADT).
“Despite clear and repeated warnings from both airports and airlines about the potential impact of this policy not being implemented, we are now faced with a stark scenario that includes the loss of 20 services and a significant number of jobs.
“This is the second example in as many months of an airline cutting capacity in Scotland because of the lack of movement on ADT.”