GENEVA (AFP) - The World Trade Organisation (WTO) is close to chosing its next leader in a final round pitting Brazil against Mexico, with the winner facing the tough task of restoring the clout of global commerce's rule-setting body.

Brazil's WTO ambassador Roberto Azevedo and his rival Herminio Blanco, Mexico's former trade minister, are expected to learn as early as Tuesday whether they have won a contest that is seen as too close to call.

All concerned are keenly aware that the successor to two-term director general Pascal Lamy from France must act fast to revive the WTO's moribund global trade talks. Both men have pitched a similar vision for a negotiating process which they say needs overhauling.

"The multilateral trading system is weakened by a complete paralysis in the negotiations," Mr Azevedo told AFP, explaining it was time to "unclog the system".

Mr Blanco, meanwhile, said it was time to reboot the 159-nation WTO.

"The main challenge is the 'W' in 'WTO'," he told AFP, underlining that the logjam had pushed members into negotiating bilateral and regional deals.

"You have to transfer this energy back to Geneva," where the WTO is based, to prove the point and reach of the organisation, he said.

Supporters of a WTO-wide deal warn that other accords can create a "spaghetti bowl" of conflicting rules, thereby failing to serve global commerce.

Created in 1995, the WTO aims to spur growth by opening markets and removing trade barriers, including subsidies, excessive taxes and regulations.

The stated goal of its "Doha Round", launched at a summit in Qatar in 2001, is to deploy trade to develop poorer economies. But members repeatedly have clashed over the give and take needed to reach a deal, with deep splits notably between China, the European Union, India and the United States.

Some have blamed Mr Lamy, a former EU trade chief, who raised hackles with an alleged name-and-shame drive to break the deadlock after he won a second term in 2009.

Amid fears that December's WTO summit in Bali could fail, the new director-general will have to act fast after taking over on September 1.

"The new DG obviously will come in at a rather precarious time for the WTO," said Mr Sergio Marchi, Canada's former trade minister and ex-WTO ambassador.

Besides working the diplomatic circuit, Mr Marchi told AFP, the new leader must repair ties with the business community - the hub of global commerce.

"The business community has taken the view, 'Call me when you're serious'... Obviously getting Doha together is a challenge, but if the institution is seen as irrelevant, it is irrelevant," he said.

"You don't have to have an agreement in your first six months, but there's got to be movement and momentum," he added.

Against that background, Mr Blanco seems to have the advantage.

The 62-year-old economist was Mexico's negotiator for the 1994 North American Free Trade Agreement and has solid private sector credentials, running an international trade consultancy and sitting on US, Asia and European company boards.

"My candidacy is a package of skills, experience, ambition and creativity," he said.

But Mr Azevedo's insider status could be key.

The 55-year-old career diplomat was Brazil's chief litigator in a raft of WTO disputes before becoming ambassador in 2008.

"In the WTO today, you don't have any low-hanging fruit. You have to go up the tree, grab the fruit and bring it down. And if you don't know the system, and don't know the trees, you're not going to get the fruit," he said.