American web users could be prevented from accessing a Napster-style music sharing site based in China if legal action by 13 major record labels is successful.

The New York Times reports that the labels, which include Sony Music Entertainment, Universal Music Group and RCA Records, have filed a suit in a New York court to try to get four ISPs to block their customers from viewing the English language Listen4ever.com website.

This is the first time the record industry has brought action against the companies that provide access to the net. In the Napster case, it was the site itself which bore the brunt of the legal action which eventually led it into bankruptcy. This time round it is the ISPs — AT&T Broadband, Cable & Wireless, Sprint and UUNet — that are being targeted.

The lawsuit is the first to invoke a provision within one of America's new laws, the Digital Millennium Copyright Act, which gives US courts the power to force ISPs to take limited action to prevent users from accessing foreign sites that break US copyright laws.

The Digital Millennium Copyright Act is one of several moves that have been made to try to protect artist's copyright across borders. The World Intellectual Property Organization has also introduced the Copyright Treaty and Phonograms and Performances Treaty, with the aim of enforcing copyright and anti-piracy laws globally.

According to the New York Times, the ISPs haven't commented on the case but an insider told the paper that they were concerned by the ease with which websites could change their names. Such dodges would leave ISPs with the tricky task of tracking down the new URLs, should they have to take on the responsibility of blocking users from these sites.