World Trade Organization talks in Geneva have collapsed after members were unable to reach a compromise on agricultural import rules.
Delegates said Tuesday the United States and developing countries were unable to settle a dispute over measures regarding protection of farmers in emerging economies.
The measures would have imposed tariffs to protect farmers in case of a sudden surge in goods on the market or a drop in prices.
Earlier, China and India accused the United States of refusing to negotiate on the issue while U.S. officials accused them of backing out of an earlier agreement.
WTO Director-General Pascal Lamy described the situation as a "serious setback" but indicated an interest in reviving talks. Trade representatives from the United States and Brazil also refused to discount future negotiations.
The current negotiations, known as the Doha Round, have made little progress towards a world trade pact since they were launched in 2001.
Disagreements between rich and poor countries have repeatedly stalled the talks.
Emerging nations have demanded wealthy countries reduce agricultural subsidies which they say give farmers in developed countries an unfair advantage in an open market.
Some information for this report was provided by AFP, Bloomberg and Reuters.