More than £200 million is lying unused by cash-strapped health trusts in England because of restrictions in the government's apprenticeship levy scheme, a study suggests.
Unison said figures based on freedom of information requests reveal that four fifths of the money has not been used, with funds now starting to be clawed back by the government.
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The apprenticeship levy is paid by all large employers across the UK, who are then able to draw on those funds to recruit apprentices. Hospitals are not able to spend the cash because they are too hard-up to take on apprentices, said Unison.
The union gathered data for the two-year period following the introduction of the levy in May 2017, with more than half of the 244 health trusts in England responding to the FoI request. Unison said its results showed trusts had paid out £256 million for the levy, but only used £54 million.
The union's head of health Sara Gorton said: "These figures are a shocking wake-up call showing the extent of the levy's failure. Hundreds of millions of pounds are sitting idle at a time when budgets are stretched and there are 100,000 vacancies across the NHS.
"There are real concerns about the standard of training apprentices receive, with many carrying out administrative and clinical support roles for peanuts.
"The NHS must be better equipped for the future. Ministers must reform the system to ensure money allocated to the health service stays within the NHS and invest properly to ensure apprenticeships play a full role in solving the growing staffing crisis."
A government spokesman said: "The apprenticeship levy means more money is available than ever before for training, giving employers of all sizes - including the NHS - the freedom to invest in the skills they need.
"We have introduced flexibilities to help employers spend their levy funds. It means employers now have 24 months to spend their levy funds and large employers are able to transfer up to 25 per cent of their funds to other businesses."