Asia is failing to contain the deadly bird flu virus and must be supported by wealthy countries to head off a devastating global pandemic, the World Health Organization (WHO) warned Friday.

While there is growing international support, WHO Regional Director Shigeru Omi said more financial and technical assistance are needed to help Asia fight the avian influenza.

He also called for greater transparency by affected countries, stressing the need for information sharing to determine if the H5N1 virus was mutating and "tipping the world into the unknown."

"The situation is that we have been losing many more battles than we have been winning," Omi told a forum of the Foreign Correspondents' Association of the Philippines here.

"The H5N1 virus has continued to claim human lives."

"Its reach is now prodigious, stretching all the way from Southeast Asia to the very doorstep of Europe. All attempts to bring it under control in the region have failed."

Since 2003, a total of 62 people, mostly in Vietnam and Thailand, have died from the bird flu virus in Asia. Tens of millions of birds have also been culled, devastating poultry industries in the region.

Omi said the world was facing a dangerous situation because the H5N1 virus is very unpredictable, firmly entrenched and spreads fast.

"The affected countries are not as well equipped to handle the threat as developing nations," he said.

He said an estimated $260 million is required by the WHO, the Food and Agriculture Organisation (FAO) and the World Organisation for Animal Health to tackle the onslaught.

So far, only $20 million have been pledged to help the affected countries in Asia - Laos, Vietnam, Indonesia and Cambodia.

Omi expressed confidence that donor countries and international agencies would be "more generous" and donate more funds to the bird flu fight in an upcoming pledging session in Geneva in December.

International experts earlier warned that global bird flu pandemic could kill as many as 150 million people.