LONDON - Britain's media regulator Ofcom has launched a review of public service broadcasting to examine how it should be provided in a world dominated by digital TV and the Internet.

Broadcasting is heavily regulated in Britain, with many of the main terrestrial providers such as ITV and the BBC expected to provide a certain amount of programming such as children's TV and regional news.

But analysts have argued that with viewers and advertisers moving to multichannel TV and the Internet, such requirements are expensive and prevent the broadcasters from competing fairly.

Ofcom said on Tuesday it would examine whether services such as the Internet could be used to deliver public service content.

"Public service broadcasting (PSB) still has an important role to play and the review will help maintain and strengthen its quality in the new market conditions," Ofcom Chief Executive Ed Richards said in a statement.

Ofcom's first PSB review in 2005 found there was a continued demand for public service broadcasting but the current provision by commercially funded channels would not survive unchanged in the transition to a multichannel world.

Britain's analogue TV spectrum is divided into five channels and licensed to broadcasters, but as the value of that spectrum declines and digital broadcasting takes over, Ofcom has said its ability to ask for certain types of programmes will diminish.

Since the last PSB review, audiences have continued to decline and Ofcom will examine whether some content could be provided via different platforms.

The publicly funded BBC provides a lot of PSB content which is available on the Internet through its free online iPlayer service. Ofcom will examine whether this is sufficient and whether other broadcasters need to provide as much PSB content.

Ofcom said it expected to complete and publish the review by 2009 and its findings will feed into a separate review by the government on the funding of public service broadcasting.