Japan officially opposed the extending the Kyoto protocol after 2012 during the ongoing global climate talks in Cancun, Mexico.

Thus, the delicately balanced talks suffered a serious setback.

"Japan will not inscribe its target under the Kyoto protocol on any conditions or under any circumstances," Jun Arima, an official in the Japanese government's Economics Trade and Industry Department, stated during an open session.

"For Japan to come out with a statement like that at the beginning of the talks is significant," a British official said as a response to Japan's move. "The forthrightness of the statement took people by surprise."

The Kyoto protocol was adopted in Japan in 1992 by 16 major emitting countries, who committed themselves to cut emissions by an average 5% on 1990 figures by 2012. It is considered a binding international treaty that commits most of the world's richest countries to making emission cuts.

The brief statement, made by the Japanese official, was the strongest yet made against the protocol by one of the largest emitters of greenhouse gases.