Updates to this story
In a move to boost its sales and compete against Android and iPhone handsets the phone giant has hired Microsoft business head Stephen Elop.
The Finnish mobile phone maker announced this morning that Kallasvuo will leave the company on 20 September. He will be replaced by Elop in an effort to "complete the transformation" of the company. Until last night Elop was the head of Microsoft's business division.
In July Nokia reported a 40 percent slump in second quarter profits, as it struggled to cope with the new boys in the smartphone market. However, since the announcement of the switch-a-roo Nokia's shares jumped up 5.8 percent.
"The time is right to accelerate the company's renewal; to bring in new executive leadership with different skills and strengths in order to drive company success," Nokia said in a statement. It said Elop would do a better job as Nokia reckons he has the right industry experience and leadership skills.
Elop was the president for Microsoft's Business Division. His responsibilities included managing the Office suite, various applications for enterprise customers and Microsoft's unified communications arm. Before that he held senior positions at Juniper Networks, Adobe Systems and Macromedia.
Poor old Kallasvuo. He's walking away with a £3.8m pay-off to cover 18 months' salary and a bonus for his efforts.