Finnish telecom giant Nokia and Microsoft plan to unveil a smartphone equipped with the US software giant's Windows 8 operating system in New York on September 5, a report says.

The Helsingin Sanomat daily did not cite any sources, but said on Wednesday the beleaguered Nokia could also unveil its first tablet computer at the event.

The Finnish company's new strategy is phasing out its Symbian smartphones in favour of a partnership with Microsoft.

That alliance has produced a first line of Lumia smartphones, which Nokia is counting on to help it survive in a rapidly changing landscape marked by stiff competition from RIM's Blackberry, Apple's iPhone and handsets running Google's Android platform.

That took a hit when Microsoft warned that existing Lumia handsets would not be able to run its Windows 8 upgrade.

The company, which in 2008 enjoyed more than 40 per cent of the global mobile phone market, was already struggling to maintain its leading position when it entered the Microsoft partnership.