The government said today it wants a new law by April 2009 obligating internet service providers (ISPs) to stop illegal file sharing on their networks. This is one of the most aggressive anti-internet piracy stances in Europe to date.

The government says that, in the meantime, it will look at "statutory solutions" that could be used until a law is in place, as well as tougher penalties for copyright infringement.

The warnings came in a report released on Friday by the Department for Culture, Media and Sport, which looks at how the UK's creative industries can be better supported.

British ISPs have been in voluntary discussions with copyright holders on ways to combat file sharing on P2P (peer-to-peer) networks but have yet to reach an agreement.

If no agreement is reached, "the government will equip itself to introduce legislation swiftly if suitable arrangements between ISPs and relevant sectors are not forthcoming or prove insufficient," the report said.

That kind of legislation would essentially require ISPs to examine what content a subscriber is downloading, opening a range of privacy concerns.

Representatives of the Internet Service Providers' Association (ISPA) could not be reached for comment, but the ISP industry generally opposes measures that requires monitoring content on their networks.

That view is supported in existing in European Union and UK directives, which says ISPs are not liable for material passing on their networks.

The UK's moves come as other European countries consider new ways to stamp out piracy. France is expected to introduce a bill shortly that will require ISPs to cut off internet access to subscribers who persistently share material under copyright without permission after receiving a warning.

Earlier this month in Denmark, a court ordered one of the country's largest ISPs to block access to a website that forms a critical part of the BitTorrent file-sharing network. The ISP, Tele2, plans to fight the order.

Music and movie industry groups have supported the creation of laws to stop piracy. FACT (The Federation Against Copyright Theft) welcomed the government's move, saying in a statement it fosters a greater respect for intellectual property.

File sharing has not only posed a legal problem for ISPs but also a technical one.

The heavy use of P2P services such as BitTorrent and eDonkey has strained networks. ISPs have contended that file sharing has degraded the quality of service for their subscribers.

Although estimates vary by region, P2P traffic can comprise between 50 percent and 90 percent of all internet traffic on an ISP's network, according to iPoque, a Germany company that specialises in appliances for ISPs to manage networks.

Comcast, a major US ISP, recently admitted to using techniques to slow down P2P traffic in order to provide more consistent service. Comcast denies blocking any content.