GENEVA — The field of candidates to lead the World Trade Organisation shrank to five on Thursday and narrowed the race to two regions, triggering a potential scramble for Africa’s support after the first of three rounds of competition.

A diplomatic source said the race now includes two Latin Americans — Mexico’s Herminio Blanco and Brazil’s Roberto Azevedo — and three candidates from the Asia-Pacific: New Zealand’s Tim Groser, South Korea’s Taeho Bark and Indonesia’s Mari Pangestu, the only woman still under consideration.

Representatives of the candidates were summoned to hear the results of the first round at a closed-door meeting in the WTO’s Geneva headquarters.

The “troika” of three WTO ambassadors presiding over the race plan to make the results public on Friday, and give a timetable for the second round, which is expected to boil the field down to a final duel, whose winner will succeed Pascal Lamy as head of the WTO on September 1 this year.

Some trade diplomats say the job is a poisoned chalice because it comes with little power to direct the WTO, a body that is run by consensus decisions of its 159 members and which is presiding over a huge slowdown in world trade and struggling to negotiate reforms in global trade rules.

However, the position is coveted because the WTO’s unusual system of treaty-based rules and dispute settlement makes it an arbiter among nations and an influential world body alongside the International Monetary Fund and World Bank.

Geneva-based diplomats have said the nine-strong race made it impossible to predict the eventual winner, especially since many governments are thought to favour candidates from particular regions.

Before the six-month process began in earnest in December, some diplomats maintained that the next head of the organisation must come from Africa or Latin America. Pascal Lamy rejected that idea, saying there was no geographical basis for the choice.

But the departure of Kenya’s Amina Mohamed and Ghana’s Alan Kyerematen means that African support is likely to become an important battleground for the remaining candidates.

The exit of Costa Rica’s Anabel Gonzalez means the two remaining Latin Americans will have to struggle for supremacy, since it is unlikely that both will survive into the final round.

The other candidate to be dropped, Jordan’s Ahmed Hindawi, was the first candidate from an Arab nation in the WTO’s 18 year history.

The draw may now favour Pangestu, who would be the first woman to lead the WTO, and Groser, who survived despite the fact that a New Zealander has held the job once before, something that was seen as counting against him.

But the WTO’s insistence on consensus means that any one member’s strong dislike can essentially be used as a veto, leaving the final outcome uncertain.