TOKYO (AFP) - A leading contender to head the World Trade Organisation (WTO) on Wednesday warned that it "is in danger of becoming irrelevant" as regional trade negotiations speed ahead while the body's global talks stumble.

New Zealand Trade Minister Tim Groser, one of five remaining candidates vying for the WTO's top post, said the next head of the Geneva-based organisation faced an "acutely difficult responsibility" because of "the glacial pace of negotiations".

"The WTO, meant to be the centre of trade policy, is in serous trouble - it is in danger of becoming irrelevant," Mr Groser told a news briefing in Tokyo after meeting with Japanese officials.

"In sharp contrast to the glacial pace of negotiations at the centre of the multilateral trading system, the WTO, the pace of developments at the regional trade policy level accelerates with astonishing speed.

"If we cannot move forward at the centre - the WTO - we will move forward in regional trade agreements, the periphery," he added.

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

Its so-called Doha Round of talks was launched in 2001, with the stated goal of harnessing global commerce to develop poorer economies, but has faltered in the face of obstacles set in particular by China, the EU, India and the United States.

The momentum has moved to regional and bilateral deals, such as the US-led trans-Pacific Partnership (TPP) trade pact, and a planned trans-Atlantic deal between the US and EU.

And the Asean bloc is expected to start talks next month on a free-trade zone that would also include China, Japan and India and cover more than half the world's population.

Supporters of a WTO-wide deal warn that regional and bilateral accords create a "spaghetti bowl" of sometimes conflicting trade rules and thereby fail to serve global commerce.

Mr Groser backed Tokyo's decision to enter into talks on the TPP, but said efforts to exclude key sectors amid opposition from Japan's powerful farm lobby would only water-down trade deals.

"Japan is far from the only country involved in TPP with sensitivities on agriculture market access," he said.

"However, we will not handle these sensitivities in agriculture, autos or whatever, by exclusions from trade liberalisation."

An unprecedented nine candidates entered the race to replace Frenchman Pascal Lamy - a former European Union trade chief who has served two four-year terms at the helm of the WTO - and emerging nations aim to stake their claim on the job which is vacant on September 1.

With four axed from the race, Brazil's WTO ambassador Roberto Azevedo is seen as a favourite in diplomatic circles.