Nokia has officially confirmed that it has dropped Wieden & Kennedy as its global marketing agency, formally ending a four year partnership with the company as it streamlines its marketing arrangements as part of a £80 million advertising campaign for its new Windows Phone devices.

Campaign reports that Nokia recently announced it would split its mobile divisions, focusing on a smart device division and a separate mobile phone division, immediately appointing new agencies to help promote its new devices worldwide. The company recently added Inferno to its global advertising account for its smartphone business and added Fallon to help promote devices in developing markets.

Nokia’s vice-president for marketing creation Steven Overman said:

Wieden & Kennedy has supported us through a significant period in Nokia’s development. The last six months has marked an important shift in our business strategy. This has naturally resulted in us continuing to evolve the relationships with our wide network of agency partners. I want to thank Wieden + Kennedy for its excellent work and contribution to Nokia’s business.

Nokia is to hold a joint event with Microsoft in Cologne, Germany on August 17 and will reportedly provide an insight into its first Windows Phone handsets, expected in October. Marketing agencies will be working closely with Nokia to ready their promotional material ahead of the launch, readying advertising campaigns to highlight the differences between Nokia Windows Phone handsets and those of its rivals.