Cash-strapped hospitals owe the Department of Health (DoH) more than a quarter of a billion pounds after taking on emergency loans to help them to balance their books.
More than 60 hospital trusts have borrowed a total of £1bn in "working capital loans" from the DoH since they were introduced in 2007, figures obtained from the department reveal.
But half of them so far have failed to pay off the full amount, and the total outstanding debt now stands at almost £270m.
The details emerged after Health Secretary Andrew Lansley claimed 22 hospitals had told his department that the payments on their private finance initiative projects were so large that they were "putting their clinical and financial sustainability at risk".
The Government's Health and Social Care Bill gets its second reading in the Lords this week.