Britain leads the world in the rate of porn downloads, according to a survey by a national newspaper.

The study for The Independent on Sunday found that just under 40 per cent of British males visited pornographic websites in 2005.

This adds up to nine million men, compared with an estimate of two million back in 2000.

The new figures show that one in four men aged 25 to 49 have visited an adult website in the past month, and UK net users search for the term 'porn' more than anyone in the English-speaking world.

The survey, which was carried out by Nielsen//NetRatings, also revealed that the number of UK women downloading pornography has risen from one million to 1.5 million in the past year. 

More than half of all children questioned also said they had found adult websites online while they were "looking for something else".

The Independent on Sunday said that its study was the first real measure of how much pornography the British consume, and that Britain is now the fastest growing market for adult downloads.