Guardian Unlimited's stranglehold on newspaper web traffic has been broken after The Sun Online overtook the page impression record the broadsheet set earlier this year.
According to ABC Electronic, in April The Sun Online received 107 million page impressions, passing the GU's 105 million at the start of the Iraq War.
Ian Clark, director of advertising at News Group Digital, said: "The audience trusts The Sun to remain true to its core values in both paper and digital editions."
Figures for GU in May revealed a 20% fall compared to March, with about 79 million page impressions per month.
Simon Walden, director of digital publishing at Guardian Newspapers, said GU had the biggest audience of unique users according to Nielsen NetRatings - standing at seven million-plus. The Sun hasn't released its equivalent figure.
He added:"I think we all know what The Sun's users are clicking on so enthusiastically."
The news came the same week as The Guardian introduced paid-for services to its web portfolio. Elements of GU now require a fee, and digital issues of The Guardian and The Observer will launch later this year.