Nokia said Friday it has entered a "broad strategic partnership" with Microsoft whose Windows Phone will now serve as the company's primary smartphone platform.
As part of a new strategic plan for the world's top mobile phone maker, which has been struggling against competition from Apple and Google's offerings, chief executive Stephen Elop also announced changes to the executive board.
The announcements were met, however, with sharp disappointment on the stock market, as Nokia's share price plummeted 9.44 percent to 7.39 euros (10.02 dollars) on the Helsinki Stock Exchange.
"Nokia is at a critical juncture, where significant change is necessary and inevitable in our journey forward," said Elop, shortly before he holds an investors briefing in London on the new strategy.
The company also said that it was creating a new 13-member executive board, with some new faces and the immediate departure of Alberto Torres, who was in charge of Nokia's MeeGo project.
The board, now called the Nokia Leadership Team, totals 13 with Elop and four newcomers - Colin Giles, Rich Green, Jo Harlow and Louise Pentland.
The briefing in London is eagerly awaited as investors hope that Elop can deliver a major shake-up, with Nokia suffering at the hands of rivals such as Apple and Google who have proved quicker at getting more innovative products to customers.
Earlier in the week, Elop warned that Nokia needed radical change if it was to survive "blazing competition" all around it.
With Microsoft Phone as the primary smartphone platform, Nokia's Symbian system will become a "franchise platform" as the company attempts to "retain and transition" its 200 million Symbian-powered mobile phone customers, it said in a statement.
MeeGo, on the other hand, will be kept for long-term development for next-generation devices.
Nokia has still not shipped any smartphones with MeeGo although the company said it hoped to have one MeeGo-related product on shop shelves later this year.
Nokia also announced a re-organisation of its business units into separate smartphone and mass-market mobile units.
"Each unit will have profit-and-loss responsibility and end-to-end accountability for the full consumer experience, including product development, product management and product marketing," the company said.