Online auction site eBay has overtaken internet retailer Amazon to become the top e-commerce site in the UK, a survey has found.

Internet ratings firm Nielsen NetRatings said eBay's UK site had increased its audience by more than 160% since March 2002 to more than six million people.

Over the same period Amazon's UK site saw its audience rise 40% to 5.2 million.

The study also found that visitors to eBay spent an average of one hour 11 minutes perusing goods, one of the longest times for any UK site.

Major achievement

EBay's online marketplace has proved to be one of the major successes of the internet.

These two companies prove that there is money to be made and that the market is growing massively Tim Roe, Nielsen NetRatings

Earlier this week the auctioneer reported that its profits more than doubled during the first three months of the year compared with the same period in 2002.

Despite falling behind eBay, Amazon's growth rate is still impressive, comfortably outstripping the 7% growth in the overall UK internet audience.

"It's not that Amazon isn't doing well - it's doing phenomenally well - it's just that eBay is doing even better," Tim Roe, senior international analyst at Nielsen NetRatings, told BBC News Online.

"To get such an enormous number of people on average spending over an hour online is an incredible achievement."

Net profit

Mr Roe said the growth of both eBay and Amazon was good news for e-commerce as a whole.

"Over the last 12 to 18 months there's been an awful lot of bad news and a lot of investment has been pulled out of the internet because people don't believe you can make money.

"These two companies prove that there is money to be made and that the market is growing massively, which contradicts what a lot of people think."