A programme to tackle the growing problem mobile phones being used to download and view images of child abuse was launched at the World Mobile Congress.

Delegates to the event in Barcelona were told that child pornography on the internet grew by 74 per cent between 2005 and 2006.

Although paedophiles usually use a PC to access these sites, the GSM Association (GSMA), which has set up the programme, said the rate of new sites accessible by mobile devices had increased alarmingly.

Part of this is due to the fact that it has been made more difficult for people to anonymously access child absue websites using their PCs. This is because of crackdowns by authorities around the world with initiatives such as Operation Ore.

Craig Ehrlich, chairman of the GSMA, said: "Whether you are a parent or not, you cannot help but be horrified by child abuse; it is a growing problem on mobile networks."

Over 50 per cent of such sites are commercial in nature, indicating a high level of involvement by professional organised crime syndicates.

The project, which also includes the EU and the International Telecommunications Union (ITU), is open to any mobile operator, irrespective of connection technology or level of sophistication.

Measures to combat the crime will include using technical mechanisms to prevent access to these websites. The sites will be identified by an appropriate agency, such as the Internet Watch Foundation.

Members will also implement 'Notice and Take Down' procedures for sites posted on their own services.

Viviane Reding, European Commissioner for Information Society and Media, said that 96 per cent of EU mobile operators had already signed up and that the stragglers were being pitched to get involved.