Parliament is demanding real-time information on the progress of government IT projects or legal action may be taken to force disclosure.
The warning was delivered last week by Sir Archy Kirkwood, chairman of a House of Commons select committee, to senior Whitehall IT directors.
If Kirkwood succeeds in his call for an end to excessive secrecy, it would mark the first major reform of the way government departments account to Parliament on the progress of major IT projects.
At a hearing of the work and pensions subcommittee last week, Kirkwood described a culture of secrecy in which civil servants and suppliers have in the past hidden behind the phrase "commercial confidentiality" to prevent disclosures about projects.
MPs on the committee said that ambitious government reforms are increasingly reliant on the success of IT.
Kirkwood's comments came during tough exchanges between the subcommittee and top executives at the Department for Work and Pensions: John Cross, formerly chief information officer of BP's IT department; Martin Bellamy, formerly of KPMG Consulting; and Kevin Bone, who had worked at IBM and NatWest bank.
Kirkwood told the officials that there was an easy and a hard way to move forward from what he called a legacy and history of secrecy, and officials who were "desperately defensive".
They were asked whether Gateway reviews of the progress of IT projects should be published. Computer Weekly has given Kirkwood's committee written and oral evidence which calls for legislation to enshrine good practice and for the publication of Gateway reviews, that are carried out in secret by the Office of Government Commerce.
Kirkwood, who heads the subcommittee and chairs the Work and Pensions select committee, praised the work of public spending watchdog the National Audit Office.
However, its reports, he said, are often written years after problems have struck a project. He emphasised the need for "some more real-time information on what is going on, as it is going on".
IT is becoming more integral to the successful development of public services and the government has an ambitious modernisation agenda, which Kirkwood said he supports.
The subcommittee chairman recognised the need for genuine commercial confidentiality. Legal action was the "hard way" to force disclosure of information. He preferred "a better system with which we can all live, that tells people what is going on so that they do not fear the worst".
In its submission to the subcommittee, Computer Weekly said the success rate of IT projects could be improved by strengthening accountability.
In independent Gateway reviews IT projects are given a green, amber or red lights.
But the reviews are confidential and adherence to their recommendations is voluntary. No report need be given to Parliament if ministers and departmental heads pass a red or amber light, or Gateway reviewers give a green light to a flawed project.
The OGC has made it clear that it does not want the reviews published. Its officials believe that the confidentiality of the reviews promotes open and honest exchanges between reviewers and departments.
But MPs believe they are not told the whole truth about the progress of IT projects.
Before systems were aborted on the Pathway benefits project at the Post Office and a scheme to develop software for the Oceanic air traffic control centre at Prestwick in Scotland, Parliament was told that both projects were progressing well.
An easy road to disclosure, or a hard one
Sir Archy Kirkwood, chairman of the House of Commons' work and pensions select committee, said, "It will not do just to sit behind commercial confidentiality.
"It is a message for the department as well as for the suppliers that if Parliament does not start getting involved in a grown-up conversation in the next six months, we will all end up with writs in court with motions for disclosure, and you will be forced to do it. That is the hard way of doing it."