Trade officials met in Geneva in November, but failed to broker a deal on subsidies ahead of the Hong Kong meeting. Those talks ended with a warning that failing to move ahead on agriculture risked jeopardizing the progress made in other trade discussions since July 2004.

The White House trade representative, Rob Portman, said on Friday that "Hong Kong will not be a time for us to make some major breakthroughs that the United States had hoped for, but we do hope that we can make incremental progress and establish building blocks that would go toward even more progress early in the new year."

He added that the United States was moving to address West African concerns about cotton subsidies, and that the United States expected some form of duty-free, quota-free access to be agreed upon for many goods from the poorest countries.

The European Union began allowing duty-free, quota-free imports in 2001 for most goods from these nations, and is now offering to eliminate its remaining barriers by 2009 on the imports of bananas, sugar and rice. Japan is also offering a broad elimination of quotas and duties on imports from these countries, although it is seeking exemptions for rice and shoe imports.

Depending on what definition or threshold is used for the world's poorest countries, 32 to 49 such countries could benefit. The Group of 7 leading industrial nations, the World Bank and the International Monetary Fund are all preparing plans to provide extra aid to help these countries' more vulnerable industries adjust to international competition.

Mr. Tsang and Mr. Lamy have each said that further progress is needed this week on broader issues like liberalizing global farm trade, lowering tariffs on industrial goods and increasing international competition in service industries like banking, insurance and transportation. But they are also calling for early understandings among ministers on trade issues involving the poor countries, and for turning these understandings into an actual agreement.

"I have placed development issues at the top of the agenda right from the outset," Mr. Tsang said Sunday afternoon, "and I would like to see an early harvest of the key development issues" at the meetings this week, "or at least see that we have made substantial progress in resolving them."