Speaking to The Times in Davos, during last week’s World Economic Forum, Dr Supachai exudes an air of calm and tenacity. It is just as well. During his time at the helm of the WTO, one of the toughest jobs in international politics and economics, he has needed every ounce of personal resilience that he could muster.

From the WTO’s Geneva headquarters Dr Supachai’s task is to wrangle the conflicting and complex negotiating positions of the organisation’s 148 member states into some sort of consensus from which progress in the trade negotiations can flow.

It is not quite mission impossible, but it is not far off — as was painfully demonstrated in 2003 when that year’s WTO ministerial talks in Cancún collapsed in a debacle which nearly scuppered the so-called Doha Round for good.

Asked what qualities the new WTO chief needs, he says: “To be persistent. To be patient — keep pushing, keep working, keep doing, keep moving.”

With an edge of frustration, he adds: “I think the quality that people sometimes accuse me of not having is to bang on the table. And I usually (say) we are not living in the Byzantine era in which you need to bang people’s heads together to get agreement. You use reason, and you use persistence, patience, getting people back.”

Still, Dr Supachai can at least now see a sunnier outlook for the trade round in the build-up to ministerial talks in Hong Kong in December.

The process remains bedevilled by complexity, and riven by tensions between some of the key trading blocs. But as the process enters a make-or-break period, Dr Supachai believes that things are looking up.

In what he sees as a symbolic testimony to constructive progress in the trade round, news breaks that the United States Government has awarded a $5 billion (£2.65 billion) contract to build a helicopter fleet for President Bush to a partly European consortium whose aircraft were designed in Britain. The WTO chief sees the surprise deal as the embodiment of the idea of a global trading system working as it should.“I would say (it is) a sincere gesture,” he says.

It is not the first sign of an easing of the stresses that have been one of the threats to a successful conclusion to the Doha Round by next year. Dr Supachai says that it also “made my day” when the EU and US agreed to open talks on ending subsidies to their aircraft builders.

Dr Supachai is optimistic that the breakthrough, brokered by Peter Mandelson, the EU Trade Commissioner, is a good omen for progress.

In an effort to keep the process on track, Dr Supachai, along with senior negotiators such as Mr Mandelson and his outgoing US counterpart, Robert Zoellick, pinpoint July as a crunch moment. By then, the Director-General wants to ensure that agreement has been reached on details about what will be negotiated at Hong Kong’s ministerial meeting five months later. He wants no repeat of the Cancún fiasco: “That’s why I have been floating the idea that we make use of the July benchmark to do a stock-taking or reality check to see how far we have got and what we have done,” he says. “By July we should have this assessment, and not in October or November — it will be too late. If they (the ministers) want to do it — it’s July.”

The Director-General emphasises a vision of constructive negotiations and says that big lessons have been learned from Cancún.

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