The Internet Watch Foundation (IWF) is to publish a list of newsgroups with names that appear to advocate or advertise paedophile content.

The group, which monitors the internet for abuse, is recommending that all UK internet service providers (ISPs) look out for, and subsequently remove the names of, the newsgroups on the list, or risk prosecution.

The list is expected to include around 50 names, about half of which are believed to regularly contain illegal material.

Newsgroup names describe their groups and are intended to link related topics to help users find what they want. The group name is often the only clue the user has about the group without reading articles from the group.

There are thousands of newsgroups and the danger is that paedophiles may use them to get in touch with each other and share information.

According to law firm Eversheds, the Child Protection Act 1978 prohibits 'taking', 'distributing', 'possessing' and 'advertising' obscene pictures of children.

The Criminal Justice Act and Public Order Act 1994 extend the provisions to 'making' pictures, so that digitally created pictures are also covered.

The definition of advertising covers anything which is "likely to be understood as conveying that the advertiser distributes or shows indecent photos".

The list of newsgroup names produced by the IWF could constitute adverts, said Eversheds lawyer Shabnam Akhtar, even if the sites do not actually contain illegal material. Simply conveying that they may contain such material is enough.

"However, there may be a number of slang terms which only a paedophile may recognise, and currently the list is restricted to names that an ordinary person would recognise," said Akhtar.

"There is a real risk that an ISP may be prosecuted if it is discovered that it has ignored the IWF's advice."