The consortium that had been interested in taking over Manston Airport has withdrawn its offer and pulled the plug on the deal.
Staff at the airport were told at a meeting this morning about the development, which represents a significant blow to those hoping the airport could be kept open.
The identity of the would-be buyer has not been revealed.
Manston Airport is facing a closure threat
Thanet North MP Roger Gale had been involved in trying to broker a deal between owner Ann Gloag and the prospective buyer, but it is not known why the potential deal has not worked out.
Sir Roger originally found the potential buyer and has been spearheading the campaign to keep the site open as an airport.
He said: "This is disappointing but it's not over yet.
Thanet North MP Sir Roger Gale with Manston Airport Chief Executive Charles Buchanan.
"There was an offer - take my word for it. It was reasonable given the circumstances, given the business has been damaged by the threat of closure.
"I know what the asking price and the offer was and there was a considerable gap between the two.
"I know what the asking price and the offer was and there was a considerable gap between the two" - Sir Roger Gale
"That offer has been withdrawn for legal reasons and whether a further offer will be made I don't know."
Sir Roger added: "I get the impression Ann Gloag wants to close the airport but if someone comes along with the asking price, maybe that will not happen."
Another glimmer of hope was offered by Sir Roger.
In a conversation he had with Ms Gloag's spokeswoman last week, her says he was told that two other people had shown an interest in the site, to keep it running as an airport.
He said: "I'm just interested in the business running as a going concern.
"I have to be careful not to raise people's hopes but the show isn't over until the fat lady sings and we have to explore every possible avenue to keep the airport open."
As a result, the airport's owner says the 45-day consultation with staff over possible closure will continue.
A statement issued by Manston Airport today said: "It is correct that the original offer to purchase Manston as an operating airport, made last Thursday at 12.15, was withdrawn late last night.
"Whether or not a further offer will be made I cannot, at least at this stage, say."
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