Microsoft Corp, which has been trailing Apple Inc and Google Inc in the fast-growing smartphone market, said it will launch Mango-powered handsets from top makers including Nokia Oyj, Samsung Electronics Co Ltd and HTC Corp in coming weeks.

The smartphone sector is currently dominated by Apple and Android phones, which together make up about half of the market, with Microsoft seen as slow to react to the rapidly rising popularity of mobile devices.

But some analysts say Microsoft still has time to catch up, especially given uncertainties among handset makers after Google's planned purchase of Motorola Mobility Holdings Inc sparked worries that Google may one day produce its own handsets.

We've seen hardware manufacturers very nervous about what Google is doing. I think anyone who turns around and competes with you is a cause for concern, Andrew Lees, president of Microsoft's Windows phone division, told Reuters in an interview in Hong Kong on Thursday.

Blackberry maker Research In Motion Ltd's recent outage problems might also ultimately help competitors such as Microsoft, analysts said.

MANGO VS APPLE, ICE CREAM SANDWICH

Microsoft sees the United States, Europe and China as its top markets for handsets based on its new Mango operating system.

As the price comes down, emerging markets do become a huge opportunity, but also the existing markets in western Europe and the U.S., because as the price point comes down, more people will get into the smartphone market, Lees said.

IDC analysts expects Android's market share to grow to more than 40 percent this year from above 20 percent in 2010, while Apple's iOS is forecast to grow to about 20 percent from about 15 percent in 2010.

The expansion comes at the expense of falling market share for Nokia's Symbian platform, expected to drop to a quarter this year from a third last year.

Lees said there were currently more than 30,000 applications for Windows smartphones, compared with about 500,000 applications in Apple's App Store.

Microsoft would introduce its Mango handsets in China for the first time next year, he said.

China is the world's biggest mobile phone market, with more than 900 million subscribers, although only a fraction are smartphone users, many of whom use Apple's iPhone and Samsung's Galaxy.

We'll be going in for the first time in 2012 and we'll be building unit volume from there, Lees said.

He declined to comment on what other vendors in China, such as Lenovo Group Ltd and Huawei Technologies Ltd, Microsoft was talking to.

We haven't announced those, but that will be an extension of what we're doing.

Microsoft would launch Samsung and HTC Mango smartphones in the United States and Europe over the next week or so, with Nokia following in various markets, Lees said.

Fujitsu Ltd has already rolled out a Mango smartphone in Japan.

Microsoft's comments come a day after Samsung and Google held the Hong Kong launch of the first smartphone powered by the new Ice Cream Sandwich operating system.

(Additional reporting by Huang Yuntao; Editing by Chris Lewis)