RYANAIR'S claims that 300 jobs at Edinburgh Airport will go as the airline axes five routes from its summer schedule have been disputed by the airport's operators.

Michael O'Leary, chief executive of the airline, also threatened further, more drastic, cuts next winter unless a deal with the airport is "extended and improved".

The no-frills operator will not fly to Berlin, Malmo, Murcia, Ibiza and Tallinn as planned from April as it reduced the number of aircraft based at the airport from seven to six, reversing five years of growth at the capital.

Mr O'Leary, chief executive of the Dublin-based airline, said the cuts would lead to 300 job losses among baggage handlers and other support staff and blamed Edinburgh's "high cost base" for the move. He claimed the planes could fly more profitably at the other 51 bases in the UK and Europe that had lower landing charges.

However, his figures were disputed by the airport's owners, BAA, which said they were not expecting any job losses and "did not understand" where Ryanair got the figure of 300 from.

The airport also played down the significance of the announcement, pointing out three of the routes – Malmo, Murcia and Ibiza – had only been announced in January and were not yet in operation.

Edinburgh Airport said it had been unable to agree Ryanair's demands be exempt from charges other airlines pay, including those for air traffic control services.

A spokesman for the airport said: "BAA has no plans to make any redundancies as a result of this announcement and we don't anticipate any jobs will be lost at Edinburgh Airport."

A source at the airport added: "BAA only employs 500 staff at Edinburgh so, even if you take into account baggage handling staff – employed separately – it's hard to square their claims."

Mike Crockart, Liberal Democrat MP for Edinburgh West, said: "BAA employs 485 staff at Edinburgh Airport and Ryanair has given an assurance none of its staff will be out of work. I am therefore unsure of where the figure of 300 has come from."

Insisting he "didn't do threats", Mr O'Leary said yesterday the number of Ryanair aircraft based at Edinburgh over winter would be halved, from six to three, unless a five-year deal with the airport was extended by October.

He said: "We've been growing for five years at Edinburgh Airport and this is the first time we've cut back in five years. There will be significant further cutbacks in the winter programme if our low-cost deal isn't extended and improved."

The announcement comes at an awkward moment for the airport, which has been placed on the market by BAA to comply with a ruling by the Competition Commission. It is due to be sold by summer.

Four consortiums are understood to be on a shortlist of bidders. These include Gatwick owner Global Infrastructure Partners, JP Morgan Asset Management, American private equity firm Carlyle Group and its Edinburgh-based banking partner Noble Grossart and a consortium led by 3i.

Ryanair now accounts for one-fifth of all flights at the airport. Yesterday's announcement will result in the number of flights it operates from the airport each week dropping by one-fifth, from 140 to 110.

Jim O'Sullivan, managing director of Edinburgh Airport, said he was disappointed by the announcement. He said: "We have tried extremely hard to negotiate with Ryanair, but sadly on many issues have not been able to find common ground. For example, we cannot accept their wish to not pay the agreed air traffic control costs all other airlines pay.

"As ever, our focus remains on providing managed, sustained and high-value growth matching the aspirations of our city."

The cuts will leave Ryanair with 300,000 fewer passengers in Scotland, taking its annual forecast for 2012 down to three million – a 10% drop compared to last year.

There appeared to be little prospect of aircraft being relocated to Prestwick – Ryanair's other Scottish base – as Mr O'Leary said there was an insufficient number of passengers travelling across the country to catch flights.