Britain could force internet service providers such as BT, Virgin Media and TalkTalk to reveal whether they restrict access to some websites at peak times while favoring others, regulator Ofcom said.

ISPs and network providers can control access to data-heavy sites, such as multi-player role-playing games, video-players and download sites to manage traffic at peak times.

Ofcom, however, said the network controls potentially could be used to block or restrict access to competitors' services or to charge for guaranteed bandwidth.

Level access to the Internet -- or net neutrality -- is a hot topic in the United States, where big broadband providers like AT&T, Verizon Communications and Comcast Corp have opposed moves by the Federal Communications Commission to regulate broadband access.

Lined up on the other side of the debate are members of the Open Internet Coalition, such as Google Inc, Inc, eBay Inc, Facebook, Skype and Twitter.

Ofcom Chief Executive Ed Richards said although the British market, with six or seven wholesale providers and dozens of retail providers, was more competitive than the United States, net neutrality had been on the regulator's radar for some time.

Some consumers had already raised concerns about traffic management, he said, and with growth in the mobile internet driven by smartphones putting more pressure on networks, it would become a bigger issue.

At the heart of this discussion is how to ensure that traffic management practices are transparent and how to ensure that traffic management is not used for anti-competitive discrimination, said Richards, launching a consultation on the subject Thursday.

He said ISPs should have to publish their traffic-management policies as a minimum, and the regulator may look at further controls, including a quality of service standard, if there was evidence of anti-competitive practices.

Ofcom's consultation will close on September 8.

(Reporting by Paul Sandle; Editing by Erica Billingham)