The United States is under pressure in world trade talks to reduce the billions of dollars in subsidies it pays to farmers each year. Leading US farm groups have vowed to fight such an agreement unless developing countries reduce their tariffs to allow in more agricultural imports.

Gawain Kripke, a senior policy advisor with Oxfam, said the United States had a greater responsibly to eliminate subsidies that depress prices for farmers in poor countries and make it harder for them to compete for export sales

"It doesn't work to demand that developing countries roll over on their agricultural sectors in order for the US to reduce its subsidies," Kripke told Reuters. "The US is sinning -- and so is the EU (European Union) -- by subsidising and dumping products on poor countries.

Also, in an era of $400 billion US budget deficits, farm subsidies "may be a luxury we can't afford," he said.

US farmers are expected to receive about $19 billion in government subsidies this year.

Phil Twyford, an advocacy director with Oxfam, said the group hoped a World Trade Organisation meeting next month in Cancun, Mexico, would focus attention "on the incredible unfairness of international trade rules."

The group will give WTO Director Supachai Panitchpakdi a petition with 3 million signatures demanding fairer treatment for farmers in developing world, Twyford said.

John Audley, director of the trade equity and development project at the Carnegie Endowment for International Peace, said the United States has a closed market for many products important to developing countries.