More than £600 million could be spent on NHS redundancies in one year as a result of the government's controversial reforms, figures show.
Estimates from the Department of Health show £616.6 million accounted for in possible redundancy costs for 2011/12.
The health service has already made £195 million of redundancy payments in 2010/11, all of which have been attributed to "the modernisation" of the NHS, documents show.
Total redundancy costs as a result of the Health and Social Care Bill, including cash already spent in 2010/11, are expected to be between £632 million and £989 million, with a government "best estimate" of £810 million.
Predicted job losses in the NHS - from April 2011 onwards - as a direct result of the reforms, which are still going through Parliament, is 9,100 to 16,800.
Howard Catton, head of policy at the Royal College of Nursing (RCN), said the redundancy costs were "huge".
He said: "This is at a time when we are having to make cuts to services which are impacting on the frontline.
"This is a huge amount of money that could be better spent, not to mention the loss of expertise and organisational memory that will result from this."
Mr Catton said hospitals could use the money to protect vital services for patients.
"Given how challenging the times ahead are for the NHS, we can ill afford to make cuts to frontline staff or lose the expertise NHS managers have in terms of tackling those challenges," he added.
RCN figures gathered from NHS trusts suggest more than 56,000 NHS positions across the UK are due to be cut, both as a result of reforms and to save costs in the long run.
The NHS has been told to find up to £20 billion in efficiency savings by 2013/14.
A Department of Health spokesman said the £616.6 million in redundancy costs was accounted for in the total cost for the reforms.
"Our planned cost for NHS reform remains exactly the same as we published in the impact assessment in September 2011.
"The short term costs are dwarfed by the £4.5 billion we will save over the course of this Parliament and £1.5 billion every year after that."
Shadow health secretary Andy Burnham said: "These eye-watering figures provide clear proof that the Tory-led government has lost control of its NHS re-organisation."
Burnham added: "It is simply unforgivable for David Cameron and Andrew Lansley to be wasting such inflated sums of money on this unnecessary vanity project when nursing posts are being lost and waiting targets are being missed.
"Scandalously, some of these pay-offs have been made to people who may end up being re-employed by Mr Lansley's new bodies.
"Today's figures are just the tip of the iceberg. They back up Labour's analysis that the government has severely underestimated the true cost of its unnecessary NHS reorganisation."
Unite head of health Rachael Maskell said: "The figure of £617 million to be spent on redundancies is yet more evidence of the wasteful nature of Andrew Lansley's deeply flawed so-called NHS reforms.
"Instead of paying off managers and shuffling them around to new posts within the Clinical Commissioning Groups, this money should be spent on frontline services and reducing waiting lists that are starting to climb dramatically because of the government's policies.
"The risk register that the government refuses to publish, we believe, contains figures that reveal the spiralling cost of the NHS reorganisation - no wonder, they do not want it to see the light of day - it is too damning.
"Andrew Lansley has become Whitehall's Captain Chaos."
Christina McAnea, Unison's head of health, said: "Despite Tory promises, the NHS is facing challenging times.
"Every penny possible should be going on patient care. Instead, as waiting lists climb and health workers lose their jobs, it is being wasted on redundancies.
"This is madness - we know many of the staff that lose their jobs will only go on to work with the new GP groups.
"It is a scandal that millions of pounds of public money is being wasted on a major NHS overhaul that no-one wants.
"Health professionals, unions, even Tory Cabinet ministers think the government should drop the Bill.
"When will they stop wasting time and money and start listening?"