The vote result on whether the Microsoft-built Office Open XML file format will become an international standard won't be officially revealed until Wednesday, the International Organization for Standardization, based in Geneva, said late Monday.

ISO is notifying its members of the result of the voting before announcing it to the general public, said Roger Frost, ISO spokesman.

The delay in the announcement adds to the tension around OOXML, which is vying to become the second office file format approved by ISO. The other is OpenDocument Format (ODF), approved by ISO in December 2006. ODF is the default file format for StarOffice, Lotus Symphony and OpenOffice.org, which compete with Microsoft's Office software.

OOXML was rejected in a September 2007 vote. Countries filed 3,500 recommendations on how the specification should be modified.

Those comments were incorporated into a modified draft during a Ballot Resolution Meeting in Geneva last month. Countries had 30 days to vote on whether they supported the new specification; that voting period ended midnight Saturday in Geneva.

A few national standards bodies have published their votes, indicating that the vote is tipping in Microsoft's favor.

The Czech Republic, Denmark and Norway switched their votes to approval from disapproval.

Finland switched its vote to approval from an abstention, while Kenya moved the other way, abstaining where it had earlier approved.

Others left votes unchanged since September: Germany approved, India and New Zealand disapproved, and Australia and the Netherlands abstained.

Unofficial reports are circulating about a number of other countries, including two, Cuba and Venezuela, which reportedly changed their votes from approval to disapproval. Several Web sites are tracking such reports to predict the results, but a definitive tally remains elusive.

Only the 87 countries that voted in September were allowed to vote in March. To become an ISO standard, OOXML must be approved by two-thirds of the national standards bodies that worked on the committee refining the proposal, ISO/International Electrotechnical Commission (IEC) Joint Technical Committee 1. Three-quarters of all voting members must also support it.

Under ISO rules, OOXML needs a double majority of the national standards bodies voting in order to become an international standard. It needs the approval of at least two-thirds of voting "P-members," committee members that participate closely in standards development, and of at least three-quarters of all committee members voting. Abstentions are not counted.

In September, it had the support of 17 of 32 P-members voting, or around 53 percent, and 51 of the 69 total votes, or 74 percent.

(Peter Sayer in Paris contributed to this report.)