Every pupil in the United Kingdom should have their own laptop computer within five years, says Microsoft chairman Bill Gates.

Speaking to teachers in London, Mr Gates launched a project which promotes the use of laptops in schools - with Microsoft providing £1m sponsorship over three years.

However the scheme's ambitious target depends largely on parents buying their children laptops and schools providing the facilities for them to be used in the classroom.

The target of all pupils having a laptop also envisages large-scale sponsorship schemes from business and fundraising activities from parents.

Providing one laptop for each school in the United Kingdom - let alone for each pupil - would cost in excess of £40m, without considering software, training or changes to classrooms.

For families who cannot afford to buy their children a computer each, there are plans for a Microsoft foundation of "e-learning" which will offer some additional assistance.

The project, 'Anytime, Anywhere Learning', which involves Microsoft and a range of computer manufacturers, is based on the principle that pupils need to have one-to-one access to technology to develop its educational potential.

"No longer is learning confined within the traditional boundaries of the classroom," said Mr Gates.

"Putting portable computers in the hands of schoolchildren will free pupils, teachers and parents ... and will ensure that future generations are technology-literate at much earlier ages."

The scheme has been piloted for two years at 28 schools. Among these, the Cornwallis school in Maidstone, Kent, has a wireless network which allows pupils to use their laptops as electronic workbooks anywhere on the school premises.