AUSTRALIANS travelling to the US will be asked to pay a $US10 ($11) fee to help fund a program to boost tourism - as well as the ailing US economy.

The fee will apply to the US ''visa waiver'' program that is mostly used by tourists and short-stay business travellers from 34 countries, including Australia and New Zealand.

Details of the fee appeared in the Travel Promotion Act, which Barack Obama signed into law late last week. The new impost is expected to raise about half the funds for a $US200 million ($220 million) global ''Come to America'' campaign.

This is the first time the US has resorted to a government-sponsored international sales pitch similar to those used by Australia and other countries to win a bigger share of global tourism.

The campaign is expected to increase visitor numbers by an estimated 1.6 million travellers, while restoring a more relaxed and welcoming image of America in a security-conscious era.