Finnish telecoms giant Nokia, the world's largest mobile phone manufacturer, announced on Monday it would launch its first-ever mini laptop.

The 'Booklet 3G' will weigh just 1.25 kilos (2.8 pounds) and will measure just two centimetres (three quarters of an inch) wide, Nokia said in a statement.

It will use Microsoft's Windows operating system and have a battery life of up to 12 hours, the company added.

The announcement comes at a time when mobile phone manufacturers such as Nokia and its Swedish-Japanese rival Sony Ericsson are facing sliding sales for their handsets.

"A growing number of people want the computing power of a PC with the full benefits of mobility," said Kai Oistamo, Nokia's executive vice president for devices.

The current global economic crisis has deterred many customers from buying new phones, while models such as Apple's iPhone and Research in Motion's Blackberry have stolen sales from the established telecom giants.

Nokia said it would announce the price and availability of its new pocket computer in September.