"Those who criticise US agricultural policy, quite rightly in my view, need a WTO deal if they want to change things and not just criticise," WTO Director General Pascal Lamy told Swiss French-language radio.
"The Americans have just voted again on massive agricultural subsidies; this is the best proof, if proof were needed, that the only way to change the US positions on agriculture and subsidies is a deal at the WTO," Lamy said.
The US House of Representatives in mid-May passed a mammoth 290-billion-dollar farm bill with a veto-proof majority, which includes subsidies for farmers and help with food bills for the needy.
US President George Bush had vetoed the bill but to no avail due to the veto override by Congress.
More From This Section
Lamy said that a comprehensive deal as part of the WTO's Doha round would offer the US fresh opportunities in market access for industrial goods and services, which could sweeten the pill of having to cut farm subsidies and cope with the attendant political problems.
The WTO's 152 member states remain mired in an impasse over the Doha round, which was failed to make significant headway since it was first launched in the Qatari capital in 2001.
Talks are stuck because of disagreements between rich and poor countries over the removal of subsidies and trade barriers for agricultural and industrial products.