BT has blocked its mobile broadband subscribers from accessing the troubled download site Pirate Bay.
The telecoms giant, which currently provides a 3G service through Vodafone's network, has taken the action after the founders of Pirate Bay were taken to court in their native Sweden.
A warning which greets BT mobile broadband subscribers when trying to access the website says: "This uses a barring and filtering mechanism to restrict access to all WAP and internet sites that are considered to have 'over 18' status'."
The guidance is in relation to a new self-regulations scheme put together by the Internet Watch Foundation.
All five major mobile broadband providers have signed up to the code.
According to reports, the Pirate Bay founders plan to appeal after being sentenced to one year in prison.