The government has reiterated its commitment to using open source software based on its "inherent flexibility" and says it will be the preferred option when cost is not an issue.
In a written parliamentary answer, Cabinet Office minister Francis Maude said the government was "committed" to using more open source software "where possible" and would "actively and fairly" consider open source alongside proprietary options when making procurement decisions based on best value for money.
"Where there is no significant overall cost difference between open and non-open source products, open source will be selected on the basis of its additional inherent flexibility," he added.
The government withheld comment on how much can be saved by transferring to open source software.
"While more open procurement can undoubtedly save money, it is difficult to ascertain precise cost savings from open source software alone as it is one element in the overall solution," said Maude.
The Cabinet Office and Office of Government Commerce are working on a "Guidance for Procurers" document, advising on open source software.
Consultations began in 2004 to consider the adoption of open source software as part of the government's continuing drive to put pressure on commercial software providers to provide the best deals to the public sector.