Microsoft Corp said it will announce an alliance with Nokia on Wednesday, likely unveiling plans to make the software company's Office suite of applications available on devices made by the world's top cellphone manufacturer.

Microsoft, the world's largest software firm, is set to bring out the latest version of its Office product next year, including an online version that will allow users to access the popular Word, Excel and PowerPoint programs over the Internet.

The move counters the recent entrance of Google Inc into the software market, offering free versions of word processing, calendar and e-mail applications online.

Microsoft declined comment on the nature of the alliance, set to be announced Wednesday morning, but an industry source confirmed the alliance concerned Office. A news report on technology site CNET news said a partnership bringing Office applications to Nokia's mobile phones was expected.

The announcement is to be made by Stephen Elop, head of Microsoft's Business Division, which makes the Office suite of applications, and Kai Oistamo, executive vice president of Nokia Devices.

(Reporting by Bill Rigby. Editing by Robert MacMillan)