ESPOO, Finland (

TheStreet

) --

Nokia

(NOK) - Get Report

shares were down 9% in European trading after the Finnish mobile phone company said it would adopt

Microsoft's

(MSFT) - Get Report

Windows Phone as its primary smartphone strategy.

Nokia, in a press release Friday, said it would adopt Windows Phone, "innovating on top of the platform in areas such as imaging, where Nokia is a market leader."

"Nokia will help drive and define the future of Windows Phone. Nokia will contribute its expertise on hardware design, language support, and help bring Windows Phone to a larger range of price points, market segments and geographies," Nokia continued.

The

announcement from Nokia

was made ahead of its analysts' day event in London Friday, when CEO Stephen Elop is expected to outline a turnaround strategy for the mobile phone giant.

-- Written by Joseph Woelfel

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Joseph Woelfel

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