Japan, trapped between the United States and the EU, which says it is ready to ratify the 1997 Kyoto pact even if the United States does not, appeared to be seeking a way out of its dilemma.
"We have not yet given up (hope) that Japan, the United States and the European Union can all participate," Chief Cabinet Secretary Yasuo Fukuda told a news conference.
Supporters of the 1997 pact, which calls for drastic reductions in carbon dioxide emissions, believe Tokyo has a crucial role in determining the fate of the agreement, which Washington has rejected but European nations support.
Japan has offered itself as a mediator between the two sides. And during his first summit with President Bush this past weekend, Prime Minister Junichiro Koizumi refrained from criticizing Bush's opposition to the protocol and sought to open the way toward future negotiations.
On Monday, Japan's Chief Cabinet spokesman, Yasuo Fukuda, appeared to support Koizumi's conciliatory line, telling reporters that revising the pact is "possible."
"We have to be realistic," he said at a regularly scheduled news conference.
But an Environment Ministry official in charge of Japan's stance on global warming denied that Koizumi's conciliatory position during the summit at the Camp David presidential retreat signaled any change in Tokyo's belief in the validity of the Kyoto Protocol.
"We're not aware of any revisions," ministry official Ichiro Kawakami said.
Japan's environment minister, Yoriko Kawaguchi, is a staunch supporter of the pact, and she has expressed anger at Mr. Bush's move to kill it. Mr. Bush has called the Kyoto Protocol, which was approved by the United States and many other countries during a meeting in Kyoto, Japan, "fatally flawed," and unfair to American companies.
Kawaguchi told reporters recently that it will be impossible to persuade developing countries to reduce their own carbon dioxide emissions if the world's biggest industrial powerhouse, the United States, won't take the lead.
Japan's opposition parties universally condemned Koizumi's refusal to pressure Bush on the Kyoto Protocol, as he suggested he would before leaving Japan for Washington on Friday. In the past, Koizumi had called Bush's rejection of the pact "deplorable."
The ministry has said Japan remains committed to reaching its own target of a 6 percent reduction in emissions by 2010, as set out by the Kyoto Protocol, despite U.S. objections to the treaty.
If Japan proposes a revision, it is likely to face fierce opposition from Europe, which is seeking ratification of the pact as it is by the 2002 target, regardless of U.S. participation, and has been pressuring Tokyo to follow suit.
Environmental group World Wide Fund for Nature (WWF) aid that Japan should move ahead without the United States.
"We have seen contradicting media reports about the talks, but we think that Japan has not changed its stance to persuade Washington," said Yurika Ayukawa of WWF Japan. "Japan should proceed and ratify the Kyoto Protocol and not set a precedent that one country can hinder an international agreement."
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