Microsoft's chief executive Steve Ballmer has announced a management reshuffle, which will see Andy Lees, who has been president of the Windows mobile division since March 2008, take on a new role straddling development of Windows Phone and the forthcoming Windows 8.

The exact nature of the role has not been specified, but was described by Ballmer as “a time-critical opportunity focused on driving maximum impact in 2012 with Windows Phone and Windows 8”.

Terry Myerson, who is currently corporate vice president of the Windows Phone Division, will step into Lees's shoes, taking over as head of the Windows Phone Division.

The news was announced in an internal email from Ballmer to staff on Monday, in which he said the changes would help “build on our momentum” from the recent launches of the Windows app store and Nokia Lumia smartphone, which runs Windows Phone 7.

“We have tremendous potential with Windows Phone and Windows 8, and this move sets us up to really deliver against that potential,” Ballmer told staff. Both of the changes take place immediately.

Lees was elevated to the position of one of Microsoft's “presidents” in October 2010, amid a massive marketing campaign for Windows Phone. The mobile operating system has so far failed to make a significant impact on the mobile market, but Microsoft's partnership with Nokia is expected to boost sales.

Meanwhile, the company's Windows 8 software, which will eventually appear on a variety of consumer-centric tablets, is not expected to arrive until the second half of 2012. The operating system will offer a “Metro” interface with touch-optimised, app-connected tiles, paired with a more traditional desktop interface; users will have the ability to flip seamlessly between the two.

Microsoft is hoping that Windows 8, together with the Windows Store, will help it catch up in the tablet race, and grab market share from Apple's iPad and slates using Google Android. However, a number of industry analysts have warned that Microsoft is coming too late to the party, and is not offering anything new.

“Windows 8 will be largely irrelevant to the users of traditional PCs, and we expect effectively no upgrade activity from Windows 7 to Windows 8 in that form factor,” said Al Gillen of IDC in a recent interview.

“Customers will be asking 'What value does Windows 8 bring to my desktops and laptops?' and the only real benefit I can see is that it provides access to the Windows app store,” he added.