"We are in the emergency stage now," Rychener, the FAO's Vietnam representative, told Reuters.

"Agriculture Minister Cao Duc Phat has authorised the FAO and the WHO to coordinate efforts to help fight the virus in Vietnam," he said.

The two UN agencies would meet donors -- Japan and the World Bank are the biggest along with Denmark, France and Britain -- along with the government and the UN Development Programme on Feb. 21, he said.

The needs were many, Rychener said.

The outbreak, which began in the Mekong Delta in December, is now infecting half of Vietnam's 64 provinces despite increasingly urgent measures to halt the rapid spread of a disease that has killed 45 people -- 32 Vietnamese, 12 Thais and one Cambodian.

Vietnam needed technical assistance, laboratory equipment and logistics expertise, Rycherner said, to fight a virus that experts fear could mutate into a form that would trigger a global pandemic and kill millions of people.

His comments came just a day after Vietnam said it had appealed for international help in its increasingly desperate battle against the virus, which arrived in Asia at the end of 2003, probably brought by migrating wildfowl.

NEW ORDER

The current outbreak is Vietnam's third since then and the virus has recurred in seven of Thailand's 76 provinces, backing up expert contentions that it is now endemic in parts of Asia and will take years -- and ruthless action -- to eradicate.

In its latest step, the Vietnamese government ordered a nationwide halt to the raising and hatching of all waterfowl, such as ducks and geese which can carry the H5N1 virus without showing symptoms.

"It is an appropriate measure," he said.

Dau Ngoc Hao, deputy head of the Agriculture Ministry's Animal Health Department, said a timetable for the suspension would be issued soon.

The government order was issued three days after Ho Chi Minh City, home to 10 million people, set a Sunday deadline for the slaughter of its more than 200,000 ducks.

The city is next door to the Mekong Delta and has set up checkpoints to prevent farmers bringing in live birds which might trigger more infections of a disease which has proven fatal to 80 percent of the people who catch it.

Almost all the victims of the virus have caught it directly from infected poultry, although a pair of Thai sisters are believed to have got it from prolonged contact with the dying daughter of one of them.

Eating properly cooked chicken, however, poses no risk, experts say.

But the longer outbreaks last and the wider they spread, the closer a human pandemic comes as the virus could mutate, probably in a pig, into a form against which humans have no immunity and sweep through the world.