By Roger Harrabin
BBC environment analyst
The Kyoto Protocol on climate change negotiated in 1997 was unfair to Japan, one of the nation's chief climate negotiators has told BBC News.
Jun Arima, lead negotiator for Japan's energy ministry, said the 1990 baseline for CO2 cuts agreed at Kyoto was arranged for the convenience of the UK and Germany.
He said if the US had stayed in the Kyoto process, it could have achieved its CO2 cuts at half the cost of Japanese industry.
And he warned that Japan would be much more cautious in future climate negotiations because it believed it had made undue concessions.
The Kyoto deal was reached at the last minute after two weeks of bruising negotiations.
Finally, Japan accepted a 6% CO2 cut, the US agreed 7% and the EU 8% - all against the 1990 baseline.
Mr Arima said: "The base year of 1990 was very advantageous to European countries. In the UK, you had already experienced the 'dash for gas' from coal - then in Germany they merged Eastern Germany where tremendous restructuring occurred.
"The bulk of CO2 reductions in the EU is attributable to reductions in UK and Germany."
His other complaint was that the 1990 baseline ruled inadmissible the huge gains in energy efficiency Japan had made in the 1980s in response the 1970s oil shocks.
"Japan achieved very high level of energy efficiency in the 1980s so that means the additional reduction from 1990 will mean tremendous extra cost for Japan compared with other countries that can easily achieve more energy efficiency."
He says it costs Japan $110 to cut a tonne of CO2, compared with $82 in the EU, and $55 in the US where energy efficiency is notoriously low so gains are cheaper.
The UK's former environment minister Michael Meacher confirmed that Japan was very reluctant to agree its 6% target during Kyoto negotiations.
He recalled that as talks reached their zenith, the Japanese climate ambassador "was mumbling into the microphone. It was impossible to follow what he was saying. And the chair said, 'I have never heard any speech which was so incomprehensible - now will you please tell us what you intend to do'. And the Japanese ambassador said, mumbling, 'we'll agree to minus 6'."
Mr Meacher agreed that the target agreed by Japan was tougher than on the other major economies, but he said Japan could easily have achieved its CO2 cuts, instead of looking to buy pollution permits from developing nations.
"The Japanese have always been leaders in technology and I don't believe that they couldn't have reduced CO2 by another 6%. All nations are trying to find some way of wriggling out of their targets. After all, 6% is not that huge - the scientists are telling us we need to reduce by 60-80%" he said.
Mr Meacher also recalled a Kyoto incident involving the former British deputy prime minister John Prescott which proved crucial in the middle of the last, long night in breaking the deadlock between the EU and the US.
Prescott, he said, approached the exhausted US climate chief in the early hours of the morning: "There was a pretty fierce exchange. John's eyes turn black and his neck swells and it's a pretty fearful prospect. And the US gave way."
The anecdote confirms that Prescott, usually depicted as a buffoon in the British media, played an important role in the development of some aspects of climate policy. This is not the only example of its kind.