Fujitsu has until the end of June to pay back the £67m it owes the NHS following the collapse of its £896m contract to help revamp NHS IT.
The service provider, which had its contract to deliver part of the £12.7bn National Programme for IT (NPfIT) terminated last month, owes the money out of £143m it received from the NHS in advance payments.
The figure emerged during a Public Accounts Committee hearing into NPfIT, where there was disagreement between the NHS and Fujitsu over the reason for the collapse of its contract to deliver the care records systems in the south of England.
At the hearing, NHS chief operating officer Gordon Hextall confirmed that BT was in the running to take over the eight sites that Fujitsu had been responsible for, with the change likely to take place in about a month's time.
Group director for UK public services at Fujitsu, Peter Hutchinson, accused local primary-care trusts of withholding payment to try and force the company to tailor care-records systems for local use.
He said: "There were a lot of delays in getting paid that were quite frustrating. A lot of trusts withheld payment in order to force us to make software changes to the system."
Hutchinson described its contract to deliver the NPfIT in the south of England as "a fight all the way" and said it had been asked to make about 615 changes.
He said: "The constant need to change systems to meet local requirements, which had not been in the contract, has been a big part of the delays."
But chief executive of the NHS, David Nicholson, questioned Hutchinson's appraisal, saying there had been debate over "what constitutes a contract change and what constitutes non-delivery of the contract".