Belgium may become the first national government to mandate the use of the Open Document Format (ODF), with a full-scale trial to begin next year.

Belgium's Council of Ministers on Friday approved a proposal that could see ODF adopted for all document exchange. The move follows similar tests by other government bodies, such as the Commonwealth of Massachussetts, and the endorsement of ODF by OASIS and its adoption as a standard by ISO, the International Organization for Standardization.

Every federal government department must be able to read ODF documents beginning in September 2007, and ODF will become the standard for external document exchange a year later, if analysis by Fedict, the Belgian e-government service, shows the trial to have been a success.

The decision leaves individual departments to decide how ODF compatibility is implemented; current possibilities include a plug-in for Microsoft Office as well as the open-source OpenOffice.org suite, which uses ODF as its native file format. Microsoft has said it has no plans to support ODF directly in Office, due to lack of demand, a decision that has attracted criticism from many quarters.

The decision leaves plenty of room for the Belgian government to change its mind. Officially, the plan endorses ODF but doesn't exclude other XML-based formats, so the government could add Microsoft's XML-based Open XML document format to the list, if it becomes convinced the format is open and standardised enough.

Other formats will be allowed for internal use, according to Fedict. And the government is free to decide against adopting ODF once the trial is complete.

Even so, the decision is a significant step, according to Thierry Stoehr, president of the Francophone Association of Linux Users (AFUL) and a prominent activist for open document formats. "This decision is a very good thing, and it should be welcomed," he said in an analysis of the announcement.

He said it remains to be seen what will come of the decision, since many significant details remain to be worked out, and because the move is likely to meet heavy opposition behind the scenes.