Despite the recent approval of the Open Document Format (ODF) by the International Organization for Standardization (ISO), Microsoft remains stalwart in its decision to forego support of ODF in its Office productivity suite, a company executive said this week.

Rather than support ODF, Microsoft is instead focusing on making XML the default file format for Office 2007, the next version of the suite that is due out later this year, said Chris Capossela, corporate vice president of Office marketing for Microsoft.

"Job one is moving to an XML-based file format, making that 100 percent compatible with every office document ever created," he said.

Microsoft's XML file format of choice is Microsoft Office Open XML, which will become the default file format for Microsoft Word, Excel and PowerPoint documents in Office 2007, Capossela said.

Microsoft wants to see Office Open XML become the international standard for office documents and submitted the technology to European standards body Ecma International in November. Ecma published the first draft of Open XML online last week. Ecma approval can help fast-track a technology through the standards process of the ISO, an international consortium that works with the United Nations to maintain and approve international technology standards.

The trouble with Microsoft's ultimate goal for Open XML is that earlier this month, the ISO approved Open XML's rival, ODF, as an international standard. Companies including Microsoft rivals Sun Microsystems, Adobe and IBM are hoping ODF will become the international standard instead. They said approval by the ISO paves the way for wider adoption of office suites that support ODF, such as Sun's own StarOffice and others, in favor of Microsoft Office.

Some analysts think the same thing, and Gartner called the ISO approval of ODF a "blow to Microsoft." The analyst firm said it's not likely the ISO will approve more than one XML-based standard for office document formats.

Capossela said that Microsoft customers are more interested in backwards compatibility between Office 2007 and older versions of the suite than they are in seeing ODF become a file format. Microsoft does not see ODF's approval by the ISO as a roadblock to customer upgrades to Office 2007, he said.