A quarter of all advertising spend is now directed through the internet, new figures have revealed.

Research by the Internet Advertising Bureau (IAB) has found that the value of online advertising climbed by 12.8 per cent last year, pushing the total electronic marketing spend to above £4 billion. The rate of growth was three times that seen in 2009.

The major growth area was display advertising on social networks, up by 200 per cent.

UK internet users devote a quarter of their online time to such networks, and advertisers have followed the trend.

Mobile advertising was also on the increase, although search advertising remained the dominant force in the market, despite a smaller growth rate of just 8 per cent.

Guy Phillipson, the chief executive of the IAB, said: "Major brands restored their advertising budgets in 2010 and online was a big winner."

Ian Barber of the Advertising Association identified the ability of online advertising to hit its audience precisely: "It's targeted, so it makes it easier for brands to work out who they're advertising to."