Internet advertising in Britain was the only ad medium to grow in 2008, rising 17% and bucking an overall industry fall of 3.5%, a report has found.
The Internet Advertising Bureau said advertising spend on the web proved resilient to the economic downturn, growing to 3.35 billion pounds as advertisers looked for greater accountability.
"These are really tough times and advertising budgets are being slashed," said the bureau's chief executive Guy Phillipson.
"More than ever, marketers have to demonstrate a clear return on their media investment, and accountability is online's trump card."
The growth makes Britain the world's most advanced market for internet advertising, with one pound in every five of media budgets spent online, the report said.
Phil Stokes, head of entertainment and media at British company PwC, said consumers were using the internet as a source of entertainment, and the quality of advertisements reflected that.
"The growth in broadband household penetration is allowing a far richer mix of video entertainment and advertising to create a `near-TV' feel for mass audiences online," he said.
"Advertisers can see new and innovative ways to build and sustain brands with targeted advertising."