Talks to sell Prestwick Airport have been placed on hold by the coronavirus crisis.Negotiations with a potential buyer have been extended in a bid to conclude the sale.The unnamed preferred bidder, understood to be AGS Airports, is hoping to take the airport back into private hands from the Scottish Government.The group also runs Glasgow, Aberdeen and Southampton Airports.Transport secretary, Michael Matheson, announced in December that negotiations had started with the unnamed preferred bidder.But it has now been confirmed that the collapse in the global aviation sector has meant discussions on the sale has been extended.The Scottish Government paid a token £1 for Prestwick in November 2013 with the airport on the verge of going bust.State