Orbital Access chief executive Stuart McIntyre said nearly £40 million lent by ministers to keep the South Ayrshire site going was likely to have caused the sale to be delayed.
His comments follow transport secretary Michael Matheson admitting to MSPs that a deal could fall through, as The Scotsman revealed yesterday.
Mr Matheson wrote: “While efforts are currently focused on returning the airport to the private sector, which has been our intention since purchasing the airport in 2013, should this not be achievable for any reason we will consider options for taking the airport forward in the future.”
The airport was put up for sale in June, with official documents stating that a preferred bidder was expected to be chosen in the first week of September and the sale completed by about 4 October.
Mr McIntyre said his bid, which was made with investors independently of Orbital Access last year, had foundered because of the Scottish Government’s unwillingness to negotiate over the sale including responsibility for the £40m debt.
He told The Scotsman: “Our submission was rejected over the pivotal matter of the treatment of the Scottish Government debt.
“It was most certainly the stumbling block, and I would not be surprised if the debt question has become the problem in the current sale process.
“It certainly appeared to be a red line - the Scottish Government was unwilling to enter any substantive negotiations over it.
“The debt has been used to cover operating losses, not for infrastructure improvements, so it has had no economic value.
“Any acquirer of the airport will need to make significant infrastructure investment to put it on a level with competitors, such as to hangars and freight facilities.
“We proposed £100 million, plus a further £200 million from third parties.
“We decided not to renew our bid. Having been through it before, there was no point in spending on further bid costs.
“The fear of strategic Prestwick-based aerospace businesses such as ours is that the Scottish Government, if a sale isn’t achieved, will consider closure or a significant scaling back of airport operations with the associated devastating impact on the Ayrshire aerospace economy.”
A spokesman for the Scottish Government’s Transport Scotland agency said: “To protect the integrity of the process, we will not be making any further comment and will update Parliament at the appropriate time.”
Ministers bought the airport for a token £1 to avert its closure and the loss of hundreds of jobs.
Mr Matheson told MSPs last week that detailed scrutiny of bids by the airport’s management was taking longer than expected.
It is unclear who has lodged bids for the site, but both Glasgow and Edinburgh airports - Prestwick’s rivals - have denied they have made offers.