TALKS between Scottish ­Government ministers and the board of the firm that owns ­troubled Prestwick Airport early yesterday morning in Shanghai paved the way for the makings of the deal to take it into public ownership.

The discussions between ­ministers and Infratil's board in the Chinese city led to an agreement that looks to have saved Prestwick from closure, which would have led to the loss of up to 1700 jobs for the local and wider economy.

Deputy First Minister Nicola Sturgeon confirmed that the terms of the sale for an as yet undisclosed amount would be on a "commercial basis", with due diligence taking place on a deal that is due to be wrapped up in six weeks.

Although the news may have shocked many travellers, a number of airports on both sides of the Border are already under public control.

One example is Manchester Airport, which is entirely owned by a consortium of local ­government which brought in its own experts to run it, creating a valuable income stream.

Prestwick, the fourth largest airport in Scotland, could follow Inverness and 10 other small airports, including Stornoway, Sumburgh, Benbecula and ­Campbeltown, which are under the umbrella of the government via Highlands and Islands Airports Ltd.

In Wales, the devolved ­administration recently took over Cardiff, while Stansted and Newcastle are also both partially public-funded.

Already Scottish opposition politicians are questioning whether public ownership will pay or whether Prestwick's inevitable demise has simply been postponed.

Aviation analyst Douglas McNeill said: "Manchester Airport is entirely owned by a consortium of local governments and the arrangement has proved incredibly successful for them.

"They've not had to pour money into it - quite the opposite. It's poured money back into their coffers.

"There's quite a few examples of local governments making a go of it by bringing in commercial experts to advise them."

However, Mr McNeill said the fear was Prestwick could follow Plymouth, which closed in December 2011, despite attempts by the local council to take it out of private ownership.

Mr McNeill warned: "Infratil are an experienced outfit and they've given it a good go, but if they haven't been able to make it work I'm not sure the Scottish Government can do differently. I'm also not convinced the traffic couldn't have been picked up elsewhere, through Glasgow, Edinburgh and north of England airports."

He said both Glasgow and ­Edinburgh Airports would have "a good look at the deal" and consult lawyers as to whether it was compatible with EU competition laws. Both have outstripped Prestwick in recent years - the capital increasingly luring away its prized Ryanair business and carving out a niche in European city breaks, while Glasgow boasts a thriving holiday market.

Neither airport was willing to comment on the development, but having a state-subsidised airport on their doorstep is unlikely to go down well, with bosses striving to attract business despite the hated airport passenger duty (APD) tax.

The writing has been on the wall for Prestwick for years. When Infratil bought the airport from Stagecoach in 2001, it paid £33.4m. Passenger numbers peaked at 2.4 million in 2007 at the height of the budget airline boom, but its reliance on Ryanair may have been its Achilles heel as the Irish operator began looking elsewhere.

In 2010, Ryanair axed its ­Prestwick-Belfast service and by 2012 passenger numbers through the airport had more than halved to 1.1 million. In March 2011, Infratil's two UK airports - Prestwick and Manston in Kent were worth £44m. A year later, the price was £32m, plummeting by November last year to £10.5m.