Ryanair is to close its base at Glasgow Airport and the number of routes operated from there will be reduced from 23 to three, with five being transferred to Edinburgh.
The airline's chief commercial officer David O'Brien said Edinburgh has a stronger "inbound component" than Glasgow with Ryanair flights.
He said 300 jobs could be lost at Glasgow due to the move with a potential fall of around 500,000 passengers.
He added the decision was down to the level of Air Passenger Duty, but also said Brexit was a threat to Scottish tourism and the airline industry.
Ryanair will only fly to Dublin, Krakow and Wroclaw from Glasgow in its winter 2018 schedule with its base at the airport closing.
It will host 45 routes from Edinburgh including 11 new routes.
Ryanair opened a new base at Glasgow Airport in autumn 2014, one of several new bases opened across Europe that year.
At the time it said it remained committed to Prestwick Airport, continuing to offer flights from there.
Ryanair carries more than 130 million customers a year on more than 2,000 daily flights from 87 bases.
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," the spokesman added.
