Putin’s stamp of approval is considered a formality, but the Kremlin has given no indication of when he will sign the pact, which seeks to slow global warming by reducing greenhouse-gas emissions. Russia’s adoption is the final step needed among major industrial countries after the treaty was rejected by the United States, which alone accounted for 36 percent of carbon dioxide emissions in 1990. The protocol needed ratification by 55 industrialized nations accounting for at least 55 percent of global greenhouse gas emissions in 1990. The pact will apply only to nations that ratify it. The U.S. government says the pact would harm the U.S. economy and also argues it favors developing nations like China and India that are big polluters, AP said.