LOSSES at taxpayer-funded Glasgow Prestwick Airport have increased to more than £7 million - amidst claims not enough has been done to diversify and bring a vital link to London.

The 2016 operating deficit at the airport, which was bought by Scottish ministers for £1 in November, 2013, is nearly £1 million up on the previous year.

It has meant that Glasgow Prestwick Airport Limited, responsible for running operations, has made total losses of £19 million in the three years since it became taxpayer-owned.

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The losses for the year to March, 2016 came as the number of passengers using the airport fell by 25 percent in a year to 624,000.

The airport now has 462,867 fewer passengers than in the year before the Scottish Government took ownership.

The Scottish Government said it wanted the airport to grow into "the successful and vibrant business we know it can be" but acknowledged that "there is no quick fix".

Laurie Price, former airline executive and expert aviation consultant said airport needed to further diversify into other business areas, including taking night mail and increasing military use while finally nailing an air link to London Heathrow. "That [the Heathrow link] would say to the world, Prestwick is open for business we we are connected to the world," he said.

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"But you have to be innovative and behave like a business not like a government.

"Someone has got to grasp the nettle and do it."

Mike Stewart, director of business development at the taxpayer-owned Ayrshire base said in January last year, that direct flights from Prestwick to London was among his priorities in the year ahead to feed a "ready market".

In his annual accounts report, director Ron Smith admitted that growing the passenger business "remains a challenge" and that there remains "significant challenges in returning the company to a sustainable and profitable operation".

While turnover remained static at around £9.3 million, he said there were "promising signs in a number of areas" including non-passenger related income.

He acknowledged a "substantial drop" in passengers numbers over the last five years, but said the indications were that things will turnaround over the next three years.

While taxpayer financial support has risen to £20.8 million in 2016 from £10.8 million in 2015, directors have accepted that the operation is only a going concern because of a commitment from Transport Scotland that it will provide funds as needed to pay for its debts.

The board said: "The directors consider that this should enable the group to continue in operational existence for the foreseeable future by meeting its liabilities as they fall due for payment.

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"As with any group placing reliance on other entities for financial support, the directors acknowledge that there can be no certainty that this support will continue although, at the date of approval of these financial statements, they have no reason to believe that it will not do so."

Mr Smith said: "Investment in our terminal and the redesigning of our passenger space will allow us to deliver a high quality service to our customers and maximise our financial performance across all of our business sectors."

Once Scotland's transatlantic gateway, Prestwick Airport now has only one passenger carrier - Ryanair.

The airport has been seeking new customer airlines to boost passenger numbers, but Mr Smith said that while the early signs were "positive" any additional revenues are not likely until late 2017.

Military aircraft handling has risen by 33 percent in the past three years and directors have acknowledge that the opportunities for growth is "significant".

It also emerged that the airport's property company, which leases out its infrastructure and other facilities made a £2.2 million loss, down by nearly £1 million in the year.

A Scottish Government spokesman said: “We have been very clear from the outset of this process that our investment in the airport is on a commercial basis, in the form of loan funding. This attracts a market rate of interest in line with state aid rules.

"A report from Audit Scotland confirmed that we are highly likely to generate a return on our investment that is higher than the current rate of interest we are charging the airport.

"There are a number of opportunities for the airport’s management team to build on, including increasing freight and passenger traffic, fixed base operations and it is very well placed to provide world class facilities for the UK Spaceport program.”

A Glasgow Prestwick Airport spokeswoman said: "The repositioning of the business will take time. We believe we are starting to move in the right direction with passenger numbers increasing, new property leases being agreed and the securing of a US government fuel contract in financial year ending 31 March 2017.

"We had forecast increased losses in Financial Year ending 31 March 2016. This was primarily due to the movement of a number of Ryanair flights to other airports. However, the losses reported are less than what was forecast in our budgets."