Russia set itself at odds with a drive by China and the United States for rapid ratification of a global agreement to slow climate change when a senior official said on Wednesday that Moscow first wanted a clear set of rules.
Negotiating a detailed rule book for the 2015 Paris Agreement for shifting the world economy from fossil fuels could take years, in the worst case, delegates said at May 16-26 U.N. talks in Bonn on implementing the pact.
Top greenhouse gas emitters China and the United States say they plan to join the Paris Agreement this year and almost all other nations say they will ratify as rapidly as possible -before the rules are in place.
But Russia, the number three greenhouse gas emitter, questioned the plan in a rare sign of disagreement about implementation.
The Agreement can still enter into force without Russia, because it requires at least 55 nations representing 55 percent of global greenhouse gases to gain legal force. Russia, the number three emitter, only accounts for 7.5 percent.