The UK Government's policy is very clear. Like many governments around the globe, it wants it's departments to consider open source seriously.

The key decisions of this policy are as follows...

• UK Government will consider OSS solutions alongside proprietary ones in IT procurements. Contracts will be awarded on a value for money basis.
  
• UK Government will only use products for interoperability that support open standards and specifications in all future IT developments.
  
• UK Government will seek to avoid lock-in to proprietary IT products and services.
  
• UK Government will consider obtaining full rights to bespoke software code or customisations of COTS (Commercial Off The Shelf) software it procures wherever this achieves best value for money.
  
• Publicly funded R&D projects which aim to produce software outputs shall specify a proposed software exploitation route at the start of the project. At the completion of the project, the software shall be exploited either commercially or within an academic community or as OSS.
  

Quoted from "OPEN SOURCE SOFTWARE Use within UK Government", 2004 October.

The original document may be found here...

• http://www.govtalk.gov.uk/policydocs/policydocs_document.asp?docnum=905

Alternatively, you can download the original document ias a printable PDF directly from here... 

• http://www.govtalk.gov.uk/documents/oss_policy_version2.pdf