DEBT-LADEN Prestwick Airport is being put up for sale by the Scottish Government after costing taxpayers around £50m.

SNP ministers bought the loss-making operation for £1 in 2013 to prevent its closure and safeguard jobs.

However they have since been forced to extend it around £50m in loans to keep it afloat.

Transport minister Michael Matheson said he wanted the facility back in the private sector.

The government has been under pressure to cut its ties to Prestwick since Nicola Sturgeon declared a “climate emergency” last month, raising questions about its ownership of a facility linked directly to greenhouse gas emissions from flights.

The First Minister’s official spokesman was unable to say if the taxpayer loans would ever be repaid, and said the airport’s debt would be part of negotiations with potential bidders.

But he said the government would aim to get “the best deal possible” for the public purse.

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An advert will now be placed in the Official Journal of the European Union inviting expressions of interest to "test the market".

Mr Matheson said: “Since the Scottish Government bought GlasgowPrestwick Airport in 2013, we have been clear that it is our intention to return the business to the private sector when the time is right.

“The senior management team at the airport has continued to engage with potential buyers and investors to discuss proposals for developing the business under new ownership.

“Good progress continues to be made by the airport to increase revenue, deliver operating efficiencies and pursue exciting opportunities for the future, including Spaceport.

“In light of that progress, the airport will shortly place an advert in the Official Journal of the European Union inviting expressions of interest.

“Any proposals submitted as a result of the advert would be considered carefully before any decision was taken to divest our shareholding in the airport or any part of the business.”

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The Scottish Conservatives welcomed the move.  

John Scott, the Tory MSP for Ayr, said: "It is good news that Prestwick Airport is now being actively marketed for sale and I hope that a buyer can be secured at the earliest opportunity.

“Despite the problems the airport has faced over recent years, and the need for it to be taken over by the government in 2013, I have always firmly believed that it has the potential for a bright future.

“Prestwick has all the foundations for success; the longest commercial runway and parallel taxiway in Scotland, a reputation of being Britain's only fog-free airport, its own dedicated railway station and a thriving aerospace campus. 

“What it now needs is an owner prepared to put in the investment to take the airport forward as the major economic asset it undoubtedly is.”

Ms Sturgeon’s official spokesman was unable to say what had prompted the move, or whether it was linked to the climate emergency.

Ministers have also been embarrassed by the failure of Prestwick’s independent management to pay the real living wage in recent years.