NHS bosses, including Airedale NHS Foundation Trust managers, are facing fierce criticism of the amount they are spending on setting up subsidiary companies to operate some hospital services.

The trade union Unison has said Airedale is spending an estimated £343,000 on establishing a company to run estates, facilities and procurement services for the trust.

Airedale has confirmed the figure, but argued that this is "money well spent", which will support the hospital's frontline services.

Unison has said a Freedom of Information (FoI) request it submitted showed trusts in England are "shelling-out" huge amounts of money on consultants.

Companies are advising trusts on the setting up of wholly-owned subsidiaries, to which staff are then outsourced, said the union.

Unison said the new subsidiary companies appeal to NHS trusts because they can reduce their VAT payments, and cut the pay and pensions for any new staff.

The union says that health workers being transferred to these companies tend to be the lowest paid, such as porters and cleaners.

Only 21 out of 31 NHS trusts approached by Unison complied with the FoI request but the amount spent by 15 of them is already more than £3.2 million.

The union's head of health, Sara Gorton, said: "The amount of public money being frittered away on transferring NHS staff to private companies is a disgrace, especially at a time when there's such a huge squeeze on resources.

"These wholly owned subsidiaries are creating a two-tier workforce where new staff are likely to be far worse off in terms of their pay and pensions.

"There is also no evidence that these new companies improve efficiency or productivity.

"Porters, cleaners and other staff chose to be part of the NHS team, not to be contracted out and treated like second-class employees."

The research was published at Unison's annual health conference in Brighton.

Shadow health secretary Jonathan Ashworth said: "It makes no sense whatsoever that NHS trusts are spending so much money transferring their own staff out of the public sector.

"This transfer of staff to effectively private companies amounts to a back door privatisation and creates a two tier workforce with fair pay and conditions undermined. Ministers should block this process now."

But a spokesman for Airedale NHS Foundation Trust responded: “Our cost of £343,000 to set up our wholly-owned subsidiary, AGH Solutions Ltd, includes insurance, solicitors, staff time and project management as well as consultancy.

"We believe this is money well spent, as AGH Solutions is growing its business to support and safeguard Airedale NHS Foundation Trust’s frontline services.”