RETAIL giant Harvey Norman will launch an online retail store within weeks, executive chairman Gerry Harvey says.

Mr Harvey, who has spearheaded a campaign by major retailers for the GST to be applied to overseas online purchases, said the time was right to go online even though it would steal sales away from his bricks and mortar stores, the Herald Sun reported.

The retailer has 173 stores nationally. However, it runs only a catalogue-style website which lists products, prices and information but has no transaction facility.

"By this time next year you'll see Harvey Norman with a pretty sizeable internet presence. My heart's beating very strongly on whether we make any money out of it," Mr Harvey said. "I haven't got any choice. I've got to cannibalise our stores."

Harvey Norman's move follows close on the heels of department chain Myer, which launched a China-based retail website this month called myfind.com, allowing Australian customers to shop GST-free.

However the Myer site has a limited range and does not compete with the variety of brands in-house.

Both retailers expect to draw back some competition from foreign sites that don't have to charge GST for purchases under $1000.

"Harvey Norman has been the pace-setter for an awful long time," Mr Harvey said. "They're kicking us on the internet at the moment but there's no history of anyone making money on it.

"I'm not against it. I'm trying to get on at the right time."

Forrester Research expects sales by Australian-based websites to soar to more than $33 billion by 2015 from $16.9 billion last year, posing a big headache for retailers who sell their goods from physical shops.