Pascal Lamy has been officially appointed as the next head of the World Trade Organisation (WTO).
Pascal Lamy has voiced his support for the world's poorest countries
The European Union's former trade commissioner emerged as the clear favourite for the role this month when his main rival withdrew from the race.
Mr Lamy, who will assume the top post at the 148-member organisation in September, faces major challenges.
He must handle an escalating trade row between China and the United States and try to secure a new free trade round.
Mr Lamy, 58, was formally adopted by the General Council of the WTO in Geneva as its next director-general, succeeding Thailand's Dr Supachai Panitchpakdi.
Always considered a leading contender for the position, Mr Lamy's candidacy became almost guaranteed when his principal rival, Uruguayan diplomat Carlos Perez del Castillo, withdrew his nomination earlier this month.
Mr Lamy is taking the helm of the organisation at a time of growing international trade tensions.
The WTO is coming under mounting pressure to quell an escalating trade dispute between China, the United States and the European Union over textile exports.
Growth in Chinese clothes exports to the west following the abolition of worldwide quotas in January has prompted the US to impose quotas on some garments amid popular calls for wider protectionist measures.
"There is no doubt that it is a difficult job," David Woods, a trade analyst, told Reuters.
"Lamy is going to need to be very clever and very patient."
As well as addressing rising tensions between China and the US, Mr Lamy will lead efforts to secure a new agreement to further reduce international trade barriers.
Mr Lamy has voiced his support for the world's poorest countries in their aim of being able to open up their markets at a measured pace.
He has said that he regards realigning the international trading system in favour of the world's least developed countries as a priority.
This commitment will initially be tested at a key meeting in Hong Kong in December when trade ministers will seek to agree a draft deal on lowering economic barriers.
Mr Lamy stepped down as the EU's leading trade official late last year. Prior to that, he was director general of the French bank Credit Lyonnais.