Toshiba plans to release the first laptop PC in the world with support for the write-once HD DVD-R optical disc format in Japan next month.

The G30/97A will be an upgrade of existing models of Toshiba's hefty Qosmio G30 entertainment laptop. Some of those models already contain an HD-DVD reader and are on sale in major markets worldwide.

The computer is based on an Intel 2GHz Core 2 Duo processor and has a 17in widescreen display with 1,920x1,280 resolution, which means it can show high-definition images from HD-DVD movie discs. The 4.8kg machine also features a 320GB hard disk drive, digital TV tuner and HDMI (high definition multimedia interface) output.

Toshiba hasn't announced a price for the laptop, which will run Windows Vista Home Premium. UK launch plans have not been announced.

To coincide with Toshiba's launch of the Qosmio laptop, Hitachi Maxell will begin selling HD DVD-R media. A single-side 15GB disc will be available in Japan from 25 January for around ¥1,500 (£12).

Another rival PC maker is also offering blue laser disc compatibility in a new machine running Vista.

NEC, which has been straddling the format fence, will put out in February two laptops with Blu-ray Disc support. The LaVie C will come out on 9 February for about ¥310,000 (£2,575) and the LaVie L will come out on 23 February and cost around ¥300,000 (£2,500). Both will be based on Windows Vista Home Premium.

The drives will be read-only models suitable for playing back Blu-ray Disc movies and other prerecorded content but not in full high-definition resolution. The computers have 15.4in widescreen displays that only offer 800 pixels of horizontal resolution. Full HD images have 1,080 picture lines.