Representatives from countries with territorial borders in the Arctic Circle, as well as Finland, Iceland and Sweden, meeting in Kiruna, Sweden, agreed to improve ways in which oil spills in the region are dealt with.
U.S. Secretary of State John Kerry said the United States was "reminded painfully" of the risks of offshore drilling by BP's oil spill in the Gulf of Mexico in 2010.
"We need to prevent disasters happening in the first place," he was quoted by the BBC as saying.
More than 10 percent of the undiscovered oil reserves and 30 percent of the undiscovered natural gas are believed to be in arctic waters. Changing weather patterns are leaving areas ice-free for longer periods, giving energy explorers access to new reserves.
China was welcomed as an observer, though Canada balked over a petition from the European Union. Nevertheless, Greenpeace policy adviser Ruth Davis told the BBC that broad membership was welcomed.
"As ministers said what happens in the arctic doesn't stay in the arctic, so it's a good step to make the Arctic Council open to new voices," she said.
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