The Motion Picture Association (MPA), which had requested the action, said that the Court had ordered BT to block access to the Newzbin2 website "and any other IP address or URL that the operators of Newzbin2 may use".
Newzbin 2 is a members-only site which collates links to a large amount of illegally-copied material including films, music and computer games, found on Usenet discussion forums.
The MPA, the international arm of the trade body which represents film studios, previously won an order preventing the original Newzbin site from linking to free content. The site later went into administration, and a new version was set up outside the UK's jurisdiction.
In July the High Court issued a landmark ruling against BT forcing it to prevent its customers accessing Newzbin2. Since then the UK's largest internet service provider (ISP) and the MPA have been in court to discuss the precise scope of the blocking measures that would have to be introduced.
The MPA, representing six major film studios - including Warner Brothers, Disney and Fox – had requested the action under Section 97A of the Copyright, Designs and Patents Act. That Act gives UK courts the power to grant an injunction against an ISP if it had 'actual knowledge' that someone had used its service to infringe copyright.
In today's ruling Mr Justice Arnold said that BT would use its Cleanfeed filtering system to "block or attempt to block" the Newzbin2 website and other web addresses that the operators may use to circumvent the block. The ISP currently uses the technology to block access to websites featuring child abuse images.
"In respect of its customers to whose internet service the system known as Cleanfeed is applied whether optionally or otherwise, [BT] shall within 14 days adopt the following technical means to block or attempt to block access by its customers to the website known as Newzbin2 currently accessible at www.newzbin.com, its domains and sub-domains and including payments.newzbin.com and any other IP address or URL whose sole or predominant purpose is to enable or facilitate access to the Newzbin2 website," the judge said in his ruling, according to a copy the MPA sent to Out-Law.com.
Mr Justice Arnold also ordered BT to foot the cost of implementing the blocking measures and rejected the firm's request for the six film studios represented by the MPA "to give a cross undertaking in damages," the High Court ruled, according to the MPA.
"In my judgment the costs of implementing the order should be borne by BT," the judge said.
"The Studios are enforcing their legal and proprietary rights as copyright owners and exclusive licensees, and more specifically their right to relief under [copyright law]. BT is a commercial enterprise which makes a profit from the provision of the services which the operators and users of Newzbin2 use to infringe the Studios’ copyright. As such, the costs of implementing the order can be regarded as a cost of carrying on that business," he said.
Mr Justice Arnold said that he "[does] not consider that a BT subscriber could bring a claim against BT for breach of contract as a result of BT’s compliance with the order".
Chris Marcich, president and managing director of the MPA in Europe, said today's High Court ruling was a "win for the creative sector".
"Securing the intervention of the ISPs was the only way to put the commercial pirates out of reach for the majority of consumers," Marcich said in a statement.
"This move means that we can invest more in our own digital offerings delivering higher quality and more variety of products to the consumer," he said.
Music and publishing industry bodies joined representatives of the film industry in backing the ruling.
Lord Puttnam CBE, president of Film Distributors' Association, said the ruling was a "very significant day for the UK's creative industries".
"The law is clear. Industrial online piracy is illegal and can be stopped," he said.
BT said that the ruling provided "clarity".
"It is helpful to have the order now and the clarity that it brings," the company said in a short statement.
The Open Rights Group (ORG), which campaigns for internet freedoms, said blocking internet users' access to content is "deranged".
"Website blocking simply will not work. It's a dangerous technological intervention when the legal markets are still a mess," Peter Bradwell, campaigner from the ORG, said in a statement.
"Consumers have moved online a lot quicker than the creative industries. The focus should be on making sure they catch up with consumer demand instead of these deranged plans to censor what people are allowed to look at," Bradwell said.
Last month Newzbin2 said that software it has developed will enable BT customers to circumvent the Cleanfeed system.
In his High Court ruling Mr Justice Arnold had said that it was "common ground" between BT and the MPA that "it would be possible for BT subscribers to circumvent the blocking required by the order".
Mr Justice Arnold also acknowledged at the time that there was evidence that Newzbin2 operators had "already made plans to assist users to circumvent such blocking".
The judge ruled that, despite the fact it might be possible to get around blocking measures "the order would be justified even if it only prevented access to Newzbin 2 by a minority of users".