Global trade talks meant to help poor countries prosper are "on the verge of failure" due to vast differences among countries, the head of the World Trade Organisation said.

The Doha Round of world trade talks has been dogged by disagreements over how far the United States and the European Union should cut farm subsidies and tariffs -- and how far major developing countries should open their markets in exchange.

"The Doha Round is on the verge of failure. Leaders of the G20 said they wanted to conclude talks by Easter, but that won't happen," Lamy told journalists in Nairobi after talks with Kenyan officials.

Leaders of the world's richest nations have identified 2011 as a "window of opportunity". Lamy said earlier this month he expected negotiators to present an initial version of a draft final agreement covering subsidies, anti-dumping rules, non-tariff barriers and other regulatory elements by late April.

Lamy blamed the lack of a breakthrough on some countries which he said preferred bilateral trade deals to a global deal.

"Big players may believe they can go the bilateral way, but most WTO members know the place they can go to where (they) can get a fairer system of international trade is the multilateral place," he said.

Since their start in 2001, the talks have stalled repeatedly, most recently in July 2008. Some experts said earlier this year that 2011 might be the last chance to secure a deal.

Countries including Mexico and Indonesia have said failure would damage the multilateral rules-based trading system that is umpired by the WTO and is credited with having prevented a return to 1930s-style protectionism during the financial crisis. (Reuters)