A video blog claiming to expose Theresa May’s plans to “flog off” NHS property has been shared by those concerned a Tory election win could result in more of the health service being sold to private companies, developers and investors.

At the centre of the controversy is the Naylor Review – a 42-page independent report, published in March, that sets out recommendations on how the Government can fund NHS reforms by selling land it no longer needs and buildings that are expensive to maintain.

When asked how the Conservatives plan to pay for their promise of “the most ambitious programme on investment and buildings and technology the NHS has ever seen”, the Prime Minister told the BBC’s Andrew Neil: “We’re backing the proposals in the Naylor report.”

Anti-privatisation activists argue the report sets out the Tories’ intention to shrink the health service and hand funds from the public purse to the private sector, through both land sales and changes designed to improve efficiency.

But health experts and analysts say the financial benefits to the NHS of selling its estimated two to five billion pounds of unused land will help secure its long-term future – and also free up sites for much-needed new housing.

The video, made by an IT specialist called Chris Holden, has been viewed more than 70,000 times and shared by health campaigners and singer Charlotte Church. The Independent has also been contacted by a number of NHS workers who say they are concerned about the issue.

“None of this stuff is hidden away. It’s all there; it’s just so mind-numbingly dull, no one wants to read it,” says Mr Holden in the clip. “This document is basically an outline plan for essentially selling off the NHS assets.”

He adds the report “makes a passing reference to maintaining and looking after old buildings, but then quite literally in the next paragraph, it says there is no business case for this, so let’s just flog everything off.”

The video blog highlights recommendations hospitals be incentivised to sell their property by receiving extra government funding, which would be restricted if they choose not to – described as a “fire sale” of NHS land.

The Naylor Review says the health service faces a £10bn infrastructure funding gap and warns that without substantial investment, NHS property, such as leaking Victorian hospitals or out-of-date IT equipment, “will remain unfit for purpose and will continue to deteriorate”.

It argues there is “no traditional business case” to justify the high cost of fixing and maintaining buildings and equipment in their current state, and instead recommends the sale of land occupied by disused services to fund reforms known as sustainability and transformation plans (STPs).

These proposals are already a thorny issue and have proved unpopular in some areas as they involve ward closures and cuts in bed numbers. Labour has promised to stop the plans, which have been drawn up in 44 areas of England.

Nigel Edwards, chief executive of health think tank the Nuffield Trust, told The Independent the NHS has “a lot of money tied up in land and buildings” and selling some of it off may not spell disaster for the health service.

“Making good use of the NHS estate can enhance healthcare and improve patient outcomes, but poor use of the estate can make being cared for a frustrating and uncomfortable experience for patients,” he said.

“The NHS is currently looking at how to make its land and buildings work better. Selling or generating income from surplus property no longer needed for patient care creates funds that can be invested to improve services. So the proposals under consideration, if done well, should help, not hinder the NHS in caring for more patients.”

However, not everyone shares this view. Activists have called the report “a clarion call for private investors” and claim it is driven by profit motivations rather than a desire to improve care for patients.

Deborah Harrington, of the National Health Action Party, set up to combat NHS privatisation, says some of the buildings labelled as “surplus” were in fact forced to close through cuts and staff shortages.

“You have the premises on which to do it, but you don’t have the staff or the money to run the service; that then becomes surplus to requirements," she told The Independent.

Ms Harrington gave the example of community hospitals in Devon, which were closed temporarily while nurse recruitment took place, because there were not enough to staff them properly.

“I said to my campaigning friends there: ‘you’re losing your hospital’ and they said: ‘No, in a rural area like ours, it’s absolutely crucial, if you don’t have these facilities there’s nowhere to go, it will be disastrous for the community’. Sure enough, that hospital’s closed, and that’s now surplus land,” she said.

Ms May said that the £10bn needed for NHS building and infrastructure projects would not be part of the £8bn extra promised in the Conservative manifesto and would come from a "variety of sources".

It was recently revealed that as well as selling NHS estates, another stream of income the health service is seeking is loans from hedge funds and private investment companies.

“There’s huge amounts of money in property, and the public purse is a perfect stream of income, basically, for anyone who can get their hands on it," said Ms Harrington.