The 52-year-old deputy prime minister and commerce minister of Thailand is a respected economist with much experience in trade negotiations. He played a crucial role in leading Thailand out of its worst economic crisis in 50 years.

He has been a strong supporter of free trade since his student days. He did a PhD in development economics under Nobel Prize-winner Jan Tinbergen at Rotterdam's Erasmus University.

His campaign has won the support of most Asian countries including Japan, a large chunk of the African nations and around half the 15 members of the European Union.

Anger at US stance

However the United States government supports his main opponent, former New Zealand premier Mike Moore, a stance which has enraged Thailand which considers itself a close US ally.

"During the Vietnam War, we were very close friends with the US", says one of Mr Supachai's aides, MP Pirapan Salirathavibhaga.

"Maybe they just forgot their old friend. The Thai people will never do that."

The US is said to object to Dr Supachai on several counts. First, North American trade unionists view Thailand as backward on labour rights.

But Dr Supachai says: "There is some misunderstanding there. I have tried to explain that this government has always fought for labour rights," he said in an interview with the English language newspaper Nation.

"I personally devoted a lot of time to the labour issue even as a university student doing my thesis."

The Americans might also be worried about Dr Supachai's record at the Thai Military Bank, which he ran from 1988 to 1992. And the US may also be concerned that Supachai would be influenced by Tokyo more often than from Washington.

Champion for poorer countries

Developing nations hope that Dr Supachai would be a champion for poorer economies and give them a stronger voice in Geneva.

He says his first priority would be to broaden the WTO and ensure the benefits of free trade are evenly spread, rather than concentrated in advanced economies.

He adds: "There are additional problems - falling trade volumes, unemployment. If trade can help solve these we can help advance the cause of international liberal trade."

However a long hard struggle to secure the top job lies ahead.