ISPs that restrict porn or block ads could be breaking EU guidelines

Sky, BT, TalkTalk and O2, which block access to adult content, could be affected - even if customers opt in

Internet service providers that restrict online access to pornography or block ads could be breaking EU guidelines on net neutrality even if customers opt in.

ISPs Sky, BT and TalkTalk already block access to adult sites following pressure from the government, as do mobile operators such as O2. Mobile operator Three has also recently run a trial of ad blocking that asked users to opt in.