Nokia has joined forces with Microsoft in an attempt to regain¹ ground lost to the iPhone and Android-based devices.

诺基亚将与微软联合作战，试图收复被iPhone和安卓机占领的市场。

The deal will see Nokia use the Windows phone operating system for its smartphones, the company said.

It means that Nokia's existing operating systems will be sidelined（退出的） .

Speaking at the launch of the partnership², Nokia's chief executive Stephen Elop revealed that there would be "substantial" job losses as a result of the tie-up.

Nokia will remain "first and foremost...a Finnish company. Finland is our home and will remain our home," he said.

But job losses around the world, including in Finland, will be inevitable³（必然的） , he added.

Windows first

Speaking about the new partnership with Microsoft, Mr Elop said that "the game has changed from a battle of devices to a war of ecosystems⁵".

"An ecosystem⁴ with Microsoft and Nokia has unrivalled（无与伦比的） scale around the globe," he said.

Microsoft's chief executive Steve Ballmer was also present at the launch, underlining the importance of the deal to the computing⁶ giant.

"Nokia and Microsoft working together can drive innovation that is at the boundary of hardware, software and services," he said.

Microsoft's Bing will power Nokia's search services, while Nokia Maps would be a core part of Microsoft's mapping services.

The new strategy means Nokia's existing smartphone operating systems will be gradually sidelined.

Symbian, which runs on most of the company's current devices will become a "franchise⁷ platform", although the company expects to sell approximately 150 million more Symbian devices in future.

"It is a transition from Symbian to Windows phone as our primary smartphone platform," said Mr Elop.

Windows may not be the exclusive operating system for Nokia tablets though.

"We reserve the right to introduce tablets using other platforms, including ones we may be working on internally," he said.

There was no specific announcement about when the first Windows-powered Nokia phone will be available.

Mr Elop revealed that the firm did consider a tie-up with Google's Android operating system.

"We spent time with our colleagues at Google and explored the Google ecosystem but we felt we would have difficulty differentiating⁸（区分） within that ecosystem," he said.

It was also revealed that talks with Microsoft only began in November, illustrating⁹ how quickly the deal has been pushed through.