Facing growing competition from open source software providers, Microsoft has decided to allow governments and international organizations access to source code for its Office 2003 productivity suite.

The company said on Sunday that it would be offering governments access to the Office code under a shared source license as part of its Government Security Program. The U.K. government has already signed up to see the code, Microsoft said.

The move is aimed at shoring up confidence in the security and interoperability of Microsoft software as it faces stiffer competition in the public sector from rivals such as Sun Microsystems, which has been touting growing support among governments for its open source productivity software, dubbed StarOffice.

In addition to responding to open source threats, Microsoft is also hoping that by allowing governments to lift the lid on Office it can diminish the mounting security concerns raised about its software.

Microsoft has long offered governments access to source code for its Windows desktop software but has made gestures recently to disclose even more about its products. Last year the company began allowing governments access to Office 2003 XML (Extensible Markup Language) Reference Schemas, enabling them to incorporate the schemas into their own software to improve the interoperability with Office documents. Under the new shared source license for Office Microsoft said it would give governments related technical information and allow program participants to discuss existing and future projects related to the software.

In addition to offering more shared source licenses, the company has also sent signals that it would be willing to cooperate more with rivals. Under a litigation cease fire deal sealed with Sun earlier this year, Microsoft said it would look for more ways to work with developers of the Open Office open source project, although it apparently reserved the right to sue them for patent infringement.

Microsoft's expansive gestures appear to be geared toward keeping a firm grip on the public sector, which often awards the largest software contracts in any country. The software maker said that more than 30 countries have already signed onto its Government Security Program, and that it has already won an adherent to the new Office shared source license in the British government.

A U.K. government spokesman said in a statement Sunday that the Office 2003 shared source license would help it understand the security implications of Office, allowing it to deploy the software more securely in a variety of scenarios.

That Microsoft has signed up the U.K. government as one of the first program participants comes as little surprise, given their historically close relationship. The U.K.'s Office of Government Commerce (OGC), which negotiates volume deals for the public sector, signed a three-year licensing deal with Microsoft in 2002 to provide desktop software for almost 500,000 public servants.

Furthermore, the government is putting final touches on a deal to renew the agreement, which an OGC spokesman characterized on Monday as "imminent."

Microsoft released news of the Office licensing program from Europe, underscoring the importance it places on winning big government deals in the region. Government bodies in Germany, Hungary, France and Italy have all recently thrown support behind open source initiatives, putting pressure on Microsoft to work harder at winning public sector contracts in Europe.