Since the end of their brutal war in 1975, the two sides have managed to resolve most of the issues that divided them and now most of their disputes are economic.

But the painful question of dealing with the victims of defoliants used by the US military is yet to be answered.

Between 1961 and 1971, the American and South Vietnamese armies used millions of litres of herbicides containing toxic dioxins to destroy jungle and crops in order to deny their communist enemies food and cover.

The dioxins ended up in the food chain and are today blamed for widespread health problems such as congenital malformation, cancers and paralysis.

In March 2002, bilateral discussions in Vietnam resulted in a draft agreement between Hanoi and Washington to mount a program of scientific cooperation.

It envisaged the setting-up of a team of researchers from both countries who would evaluate the impact of the defoliants.

Dr. Anne Sassaman, an American scientist from the US Department of Health and Human Services, took part in that process and even returned to Vietnam in November to meet several Vietnamese officials.

But today, practical research is still a long way off.

"There is much work ahead in establishing processes for funding and guiding research," she told AFP.

"Furthermore, the US and Vietnamese sides must agree on issues of scientific methodologies, scientific policy review, and transparency ... in order to establish mutually satisfactory arrangements concerning conditions under which research findings will be reviewed, published and made available to the international scientific community."

But one of her Vietnamese counterparts put it more directly.

"There are some very minor cooperative projects between the two countries, but no agreement on the (major) questions has been concluded or signed," said Nguyen Ngoc Sinh of the Ministry of Natural Resources and the Environment.

The composition of the Vietnamese team has still not been provided to Washington, signaling what some observers suggest are divisions in Hanoi over its position and priorities.

"It was difficult to believe that the two countries had managed to find an an agreement," said one foreign diplomat familiar with the issue.

"The United States wants to carry out an epidemiological survey of great scope which is expensive, whereas the Vietnamese consider it useless," he said.

The survey would help establish the number of victims. The Vietnamese say anywhere between hundreds of thousands and two million people have been affected, but the US is reluctant to estimate a figure.

"There are many factors in a developing country such as Vietnam which contribute to the health problems blamed on Agent Orange. Unfortunately, I understand that to date there has been little interest (in Vietnam) in dealing with some of these other public health issues," said Dr. Sassaman.

Although it has not asked directly, Hanoi has long sought the payment of damages by Washington for the victims of Agent Orange, but the US has argued that Vietnam dropped its calls for compensation when the two countries normalised ties in 1995.

Certain members of the Congress have even accused Vietnam of turning the issue into a propaganda tool in order to obtain money from Washington. The US has so far stuck to its position of providing only humanitarian aid to victims.

Some 7,500 American Vietnam veterans have already won the right to monthly payments of compensation for diseases linked to Agent Orange, a legal precedent which would be expensive if extended to Vietnamese sufferers.

"If the link between people with symptoms of dioxin poisoning and Agent Orange were proven, and if compensation was calculated on what was obtained by American veterans, that would be quite a significant (amount of money)," said one observer.

On Thursday, the British publication Nature reported the quantity of dioxin contaminated herbicides used during the conflict had been underestimated by at least ten percent.

"All the statistics will never reflect the situation in our country," Hanoi's Foreign Ministry answered, adding that the US should assume its "responsibilities".

"It must be pointed out that no country has suffered from Agent Orange as much as Vietnam," the ministry said.

And while the wait for a methodology which suits both sides continues, the victims remain in the hands of non-governmental organisations.

SPACE.WIRE