More than 20 countries agreed to phase out coal power at the U.N. climate talks in Scotland, but not Japan — a "leap backwards" for a country that once led the way on the Kyoto Protocol to reduce greenhouse gas emissions.

The pact was among a raft of pledges made at the COP26 summit in the last week. Japan, the world's third-biggest importer of the dirtiest fossil fuel, declined to sign because it needed to preserve all its options for power generation, officials said.

Critics called that short-sighted, even as the new prime minister, Fumio Kishida, has agreed to step up other environmental measures.