Johannesburg, South Africa ? Russia announced Tuesday it will ratify an accord on reducing smokestack emissions and other causes of global warming. Moscow’s approval would clear the way for the agreement to become law in much of the world but not the United States.

Russia’s promise on the agreement, which the United States has rejected, came as leaders at the World Summit wrapped up a long-term blueprint for tackling the global woes of poverty and pollution.

The United States continued to be criticized for its rejection of the Kyoto Protocol, which requires developed nations to reduce emissions of carbon dioxide and other heat-trapping gases to 1990 levels by 2012. Many countries view the accord as crucial to reversing a global warming trend blamed for cataclysmic storms, floods and droughts worldwide.

“All countries around the world need to address the questions of environmental protection … under the same rules,” said Japanese Prime Minister Junichiro Koizumi.

Russia’s ratification of Kyoto would meet the last requirement for the accord to come into effect: that the countries on board account for at least 55 percent of carbon dioxide emissions based on 1990 output.

Once that happens, the nations that have accepted it 87 so far would be required by law to start reducing the carbon dioxide and other gases pumped out by factories, cars and other sources thought to trap heat in the atmosphere, warming the Earth.

The United States, which rejected the accord last year, would not face the requirements, which the Bush administration says would set back the U.S. economy.