Australian Health Minister Tony Abbott said on Sunday Australia was willing to offer more aid to neighboring countries to combat the spread of bird flu, aware of the implications for international travel and for Australians abroad.

Australia has already given Indonesia 50,000 courses of the antiviral drug Tamiflu, which is considered the first line of defense against the H5N1 avian flu virus because it can reduce the severity of influenza and may slow its spread.

"In respect of helping our neighbors, we've already invested some A$15 million (US$11 million) in surveillance and preparation in Indonesia, we've invested another A$15 million around other countries in the region," Abbott told Australian television.

"We will look at what more needs to be done to build up international stockpiles. All reasonable steps will be considered and so far all feasible steps have been taken," he said.

Abbott pointed out that international travel to and from countries where bird flu was known to be present would likely become extremely difficult if not impossible if the virus mutates to allow the easy spread of the disease from human to human.

Restrictions could make it difficult for the more than 160,000 Australians who are visiting or living in Asian nations at any one time to return home, the Department of Foreign Affairs said on Friday.

"If there is a pandemic, international travel will almost cease, I suspect for a significant period of time," Abbott said.

The federal government would do its best to allow Australians living or traveling overseas back into the country should a global bird flu pandemic strike, he said.

"I believe that if we do have a situation like this, Australians abroad will want to come home and we will do our best to facilitate that," he said.

The government has warned that expatriates and travellers should have their own supply of antiviral drugs and have an evacuation plan in the event of an outbreak. The warning covers virtually all of East Asia.

The H5N1 strain of bird flu has killed more than 60 people in Asia since the disease re-emerged in 2003.

No human cases have been reported in Australia but antibodies were recently found in three pigeons imported from Canada. The birds, which did not actually have bird flu, were destroyed.