Microsoft CEO Steve Ballmer has asked Andy Lees, president of Microsoft’s Windows Phone division, to move to a new role at the company.

Lees will continue to report to Ballmer in a new role related to Windows 8. All Things Digital obtained an internal memo from Microsoft CEO Steve Ballmer on Monday. “I have asked Andy Lees to move to a new role working for me on a time-critical opportunity focused on driving maximum impact in 2012 with Windows Phone and Windows 8,” Ballmer said. “We have tremendous potential with Windows Phone and Windows 8, and this move sets us up to really deliver against that potential.”

The move will see Terry Myerson, corporate VP of Windows Phone Engineering, take over some of Lees responsibilities, including business development, marketing and other responsibilities. All Things Digital reports that Myerson will not be granted the president title of Windows Phone. Ballmer praised Lees’ efforts, despite the slow progress of Windows Phone 7. “In the three years Andy has been leading the phone group, we’ve come a long way,” Ballmer said. “We reset our strategy, built a strong team that delivered (Windows Phone 7) and (the Mango update) and created critical new partnerships and ecosystem around Windows Phone. That is a ton of progress in a brief period of time, and I’m excited for Terry and team to keep driving forward and for Andy to dig into a new challenge.”

Lees previously outlined Microsoft’s vision for combining Windows and Windows Phone. Lees spoke at a keynote address during Microsoft’s Worldwide Partner Conference earlier this year. Lees explained that there are key trends that are fundamentally changing the world of devices and form factors. “It starts right at the core of the devices themselves, the core technology,” he said. Lees reflected on Microsoft’s first Windows 8 demo at CES. “The motherboard was smaller than a phone” said Lees. “You can put all of the key things required to run a computer into a single chip.” The system-on-a-chip transformation will assist in the form factors of PCs explained Lees. “We won’t have an ecosystem for PCs and an ecosystem for phones, one for tablets. They’ll all come together,” he explained. “It’s not that this is about replacing the PC, and that’s why our strategy is that these new form factors are within a single ecosystem and not new ecosystems themselves.”

Lees’ new role appears to be working towards Microsoft’s vision for a single Windows ecosystem across multiple devices. Microsoft is currently preparing its Windows 8 operating system which will include support for the latest ARM chipsets and a new range of touch enabled form factors.