Nokia has joined forces with Microsoft in an attempt to regain ground lost to the iPhone and Android-based devices.
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.
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 ecosystems".
"An ecosystem with Microsoft and Nokia has unrivalled 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 computing giant.
http://www.bbc.co.uk/news/business-12427680
Note: 11 February 2011 Last updated at 09:41 GMT