Online advertising spend in Britain totaled 917.2 million pounds ($1.72 billion) in the first half of 2006 - 40.3 percent more than in the year-earlier period, according to a new study by the Internet Advertising Bureau in the U.K.

The study, carried out by PricewaterhouseCoopers for the IAB, found that the internet is the fastest-growing advertising medium in the U.K., Reuters reports. Internet ad spending continued to grow despite a weak overall market and is predicted to overtake ad spending in the national press before the end of 2006.

The internet accounted for 10.5 percent of U.K. ad spend in the first half - nearly half of TV's share, and up from 7.3 percent for the same period last year, reports the Guardian (U.K.). Internet ad spend is now double that of outdoor in the U.K .(5.1 percent), more than twice that of consumer magazines (4.6 percent) and three times the size of radio (3.4 percent).

Paid search was up 57.7 from the year-earlier period, reaching 531.3 million pounds and accounting for a 57.9 percent share of online ad spend. Online display advertising was up 32.2 percent, to 215.9 million pounds, accounting for a 23.5 percent share of internet ad spend.

ZenithOptimedia on Monday said more would be spent on online advertising this year globally than on outdoor advertising, and online could soon pass radio as well. It said growth is being driven by smaller brands' using the internet to effectively target their markets, for less.