In the 12 years that we've been shopping on the internet, UK online retail sales have accounted for a whopping £100 billion ($197 billion).

The Interactive Media in Retail Group said online sales of £3.47bn were recorded for April 2007, indicating that the total for internet sales to UK shoppers would hit £100 billion this month.

IMRG believes the UK's first secure online shopping transaction was the purchase of a book from WH Smith via CompuServe, a forerunner of the internet, in April 1995. The bookseller launched its CompuServe store that month with 250 books and CD-roms.

April saw the IMRG's online sales index rise 55 percent on the previous year's figures, the largest annual rise since December 2003. This growth in UK online shopping revenue was much higher than the average year-on-year growth rate of 32 percent for the past 12 months.

David Walmsley, head of web selling for John Lewis Direct, said: "For the year to date we have seen growth of 44.9 percent compared with the same period last year."

The store had seen strong online sales growth in the first quarter of the year, driven by its Home ranges, he said.

"However there have been tougher conditions around some technology categories such as televisions, where the growth bubble from last year is now flattening out," he added.

IMRG managing director Jo Evans said: "This is an astonishing landmark. It's been obvious for a couple of decades that a secure, networked consumer marketplace would arrive and be popular, but actually witnessing its profound success and meteoric growth still takes my breath away."

April's online sales were worth about the same as takings in London's West End for a year, she added.