Internet advertisers need to increase the standard of their campaigns, it has been suggested.

Lord Borrie, chairman of the Advertising Standards Authority (ASA), commented: "The boundaries of regulatory responsibility online are still unclear."

"The industry needs to address this issue quickly so that consumer faith in online messages can be as high as it is for advertising that appears in traditional formats," he added.

Lord Borrie's comments follow research from the ASA revealing complaints about online advertising rose by a third over the course of 2006.

However, television and national newspaper adverts attracted more complaints last year.

Last month, a study by the European Interactive Advertising Association revealed that marketers are increasingly using 'entertaining' adverts in an attempt to attract online readers.

Both video streaming and super banners were said to be popular for advertisers in terms of enhancing greater "user experience and retention".