Microsoft chief executive officer Steve Ballmer unveiled a new tablet computer from Hewlett-Packard while announcing closer integration with the world's top computer manufacturer.

Mr Ballmer, in the opening keynote speech at the annual Consumer Electronics Show in Las Vegas, said the new device, which he described as a "slate" computer, will feature Microsoft's latest Windows 7 computer operating system.

"It's a beautiful little product," Mr Ballmer said, displaying what he called a "prototype of a coming HP slate PC".

"Slate PCs that will be rolling into the marketplace this year... are "perfect for reading, for surfing the web and for taking entertainment on the go," he said.

Mr Ballmer said the HP device and others in what he called an "emerging category" of personal computers would be available later this year. Mr Ballmer's unveiling of the HP "slate" came as Microsoft rival Apple is reported to be poised to unveil a tablet computer of its own, perhaps later this month.

In his speech, Mr Ballmer announced closer cooperation with HP on other fronts with the number one computer maker adopting Microsoft's new Bing search engine and MSN homepage.

"Microsoft and HP will team up on the search and web portal experiences," added Mr Ballmer.