Delegates from 130 nations yesterday concluded their first meeting on global warming with an agreement to focus future negotiations on "appropriate commitments" to reduce carbon dioxide and to provide financial aid to developing nations that forgo use of the most polluting fuels.

The agreement represents a small concession by the United States, which entered the talks 10 days ago hoping to avoid negotiations over specific targets and financing mechanisms to control emissions of industrial gases blamed for trapping solar heat and warming the planet. Carbon dioxide is the most common of those gases.

But, critics of U.S. policy said, the term "appropriate" -- reportedly inserted at the insistence of the White House -- is broad enough to forestall exacting requirements in any final agreement.

Moreover, U.S. delegates prevailed in the Bush administration's preference for tapping ongoing environmental programs by international organizations -- rather than creating new ones -- to help developing nations avoid burning fuels that create warming gases.

"It doesn't make sense to write blank checks when there are billions of dollars already spent on development issues and not all spent sensibly on the environment," said Michael R. Deland, chairman of the White House Council on Environmental Quality.

The agreement was reached on the final day of an organizational meeting of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change, convened by the United Nations.

Negotiators hope to reach an agreement over the next 16 months. But national goals vary widely, with Washington seeking to form a consensus on the severity of the problem and remedies for it, while European governments want specific timetables and targets for reduction of the carbon dioxide.

U.S. delegates opposed the singling out of carbon dioxide because its source -- mainly coal and oil -- fuels the engines of industry and electric utilities. In yesterday's agreement, negotiators also promised to focus on other warming gases, such as methane, which Washington believes will be less costly to reduce than carbon dioxide.

Deland called the agreement a "substantial step forward." But environmentalists monitoring the talks in Chantilly, Va., criticized the slow pace of negotiations.

"They spent 10 days discussing the shape of the table without getting down to save the Earth from global warming," said Dan Becker, of the Sierra Club.