INTERNATIONAL tourists will be able to buy pre-pay Oyster cards online before they arrive in London.

Initially the smartcards - which can be used on Tube, bus, DLR and tram journeys - will go on sale in India, Hong Kong, Singapore, Spain, Portugal and the USA via VisitBritain's website.

Eventually, the cards will be sold in all 36 countries targeted by VisitBritain.

It's hoped the initiative will boost tourism in the capital.

Mayor of London Ken Livingstone said: "Oyster is already a proven success with Londoners and this new deal will make it easier for millions of overseas visitors to get around London.

"The best way for visitors to travel around the capital is usually by public transport so this deal will provide simpler, cheaper and quicker journeys."

VisitBritain will be selling the cards in multiples of £10 and £20 with each card holding a maximum of £90.

VisitBritain's director of commercial and marketing services Kenny Boyle said: "With more than 12 million visits to our overseas websites every year, Transport for London and other commercial organisations recognise that VisitBritain can help them reach new customers.

"By creating platforms, such as our online shops, we can help tourism businesses - large and small - attract more custom."

Currently the smartcards can only be used at Tube stations and on some buses, but it was announced earlier this year that by 2008 all mainline stations will have Oyster card facilities.

Oyster was introduced in 2003 and there are currently 5 million users in the capital.

The pay-as-you-go scheme makes travelling cheaper for passengers than with cash.