"There is a growing demand among the British population for flexibility in their media consumption," said Neal McCleave, managing director of media services at Tiscali UK

"As broadcasters worry about the fragmentation of the media audience, they need to look to on-demand television which is proving itself capable of retaining audience share and growing viewing times."

The report, entitled Tiscali TV Trends 2008, found that 37% of UK viewers regularly watched on-demand content, an increase from 17% in 2006.

86% of the consumers who watched TV on demand in 2007 were viewing as many or more programmes than they did in the previous year.

63% of the people watching TV on-demand view the content on TV sets, with 38% using PCs.

Reasons given by viewers for using on-demand included catching up on a missed programme (58%), overcoming schedule clashes (39%) and flexibility (49%).

Londoners lead the country in the use of on-demand -- 26% say they use it daily and 29% weekly.

The move to on-demand viewing is being driven by broadcasters and telecoms companies, who all have competing offerings in the marketplace.

The BBC has notable success with the iPlayer, while Channel 4, Sky, Virgin Media and BT Vision are also pushing on-demand.

Tiscali, publishers of the report, also offer an on-demand TV service that delivers programmes over the internet.

"Tiscali TV has been developed for consumers who want more choice and flexibility than Freeview, but don't see the value in paying over the odds for satellite or cable services," said McCleave.