"Mobile phone chip designer Arm has announced an alliance with the makers of the Ubuntu open source software. The deal will produce a version of the operating system for small net-browsing computers known as netbooks.

It marks a departure for Arm, which before now has been best known for designing the chips inside smartphones and feature phones. The new operating system for Arm-powered machines looks set to be available in April 2009.

Rob Coombs, director of mobile marketing at Arm, said he expected to see the first devices running the version of Ubuntu by the time of the Computex show in June.

The devices will be based around the Arm7 architecture and, in particular, the Cortex A8 and A9 processors. "It's significant in that it is taking Arm onto larger screen formats," he said.

The resultant netbooks were likely to sport screens up to 25cm (10in) across and be able to run good quality video, web browsers, and the well-known suite of Open Office programs, said Mr Coombs.

Equally, he said, these netbook devices would have the long battery life enjoyed by many mobiles. "They'll be for people who want a small internet-centric device," he said.

In a statement Jane Silber, head of Canonical, Ubuntu's commercial sponsor, said: "This is a natural development for Ubuntu, driven by the demand from manufacturers for an ARM technology-based version."