Microsoft said Thursday that it has reached a deal with the One Laptop Per Child project to make its Windows XP operating system available on the group's low-cost notebook computers for distribution to students in developing countries.

"By supporting a wide variety of affordable computing solutions for education that includes OLPC's XO laptop, we aim to make technology more relevant, accessible, and affordable for students everywhere," Craig Mundie, Microsoft's chief research and strategy officer, said in a statement.

Microsoft will charge OLPC a highly reduced Windows XP licensing fee of $3 per unit under a program it calls Unlimited Potential. OLPC's goal is to make the XO widely available to students in poor nations for a total price of less than $100.

OLPC said it now plans to offer XO models with both the Windows XP and Linux operating systems. "Today's announcement, coupled with future plans for a dual-boot version of the XO laptop, enhances on our ability to deliver on this vision," OLPC chairman and founder Nicholas Negroponte said in a statement.

Negroponte added that OLPC would work with "third parties" to port the XO's open source Sugar user interface to Windows XP. Sugar features numerous tools and miniapplications that students can use to create content and music, interact with friends and teachers, and browse the Web.

The plan isn't without controversy.

Sugar was developed by Sugar Labs. Founder Walter Bender recently left the OLPC project over differences with Negroponte concerning the project's direction. The rift could hinder OLPC's plans to port Sugar to Windows XP. "There's a lot of engineering and it's not clear that it's the best use of engineering resources," Bender told BBC News on Friday.

However, some educational officials said adding Windows to the OLPC XO is a practical move. "Windows support on the XO device means that our students and educators will now have access to more than computer-assisted learning experiences. They will also develop marketable technology skills," said Andres Gonzalez Diaz, governor of Cundinamarca, Colombia.

Microsoft said OLPC is planning to start testing Windows XP on the XO starting in June.