Secret talks among top environmental negotiators from the so-called Umbrella Group of industrialized countries, originally scheduled for mid-February in New Zealand, have been postponed until some time in the latter half of March, informed sources said Sunday.

The sources said that the secret New Zealand meeting of Japan, the United States and eight other non-European Union industrialized countries has been put off to allow the new Republican administration of U.S. President George W. Bush time to review the global warming policy of the administration of former Democratic President Bill Clinton.

Bush formally took office on Jan. 20. The Umbrella Group comprises Japan, the U.S., Canada, Australia, New Zealand, Iceland, Norway, Russia, Ukraine and Kazakstan.

At their New Zealand meeting, the new date for which has not yet been set, the Umbrella Group nations will try to hammer out a joint strategy toward stalled international negotiations on ways to prevent global warming, the sources said.

The meeting comes about four months after the failure of the sixth Conference of Parties to the United Nations Framework Convention on Climate Change, or COP6, in The Hague.

After marathon all-night negotiations in late November, COP6 collapsed due to sharp differences over details regarding the use of "sinks" and other complex mechanisms for helping industrialized countries reduce carbon dioxide and five other types of greenhouse gases, which are widely blamed for global warming.

COP6 is scheduled to resume in Bonn in late May. However, the U.S., the world's largest producer of greenhouse gases and the country that is widely believed to hold the key to the success of COP6, said last week that it wanted the resumption of the Bonn conference to be delayed at least until July because it needs time to review its policy toward COP6.

Sinks are defined as active efforts to manage ecosystems through the use of carbon dioxide-absorbing forests. But the devil is in the details, and it remains to be seen if some 180 countries will be able to nail down the details on those mechanisms.

The U.N. convention was signed at the 1992 Earth Summit in Rio de Janeiro. At COP3 in Kyoto at the end of 1997, the U.N. convention signatory countries adopted the "Kyoto Protocol," which set legally binding targets for industrialized countries to reduce their total volume of greenhouse gas emissions by 5.2 percent from 1990 levels on average for the period from 2008 to 2012.

The protocol specifically requires Japan to slash emissions of greenhouse gases by 6 percent, the U.S. by 7 percent, and the 15-nation EU by 8 percent during that period.

Although the introduction of sinks and other mechanisms, including the "emissions trading," were agreed upon at COP3, no final agreement has been reached on the details of the mechanisms, even among industrialized countries.

The Umbrella Group countries, which have generally similar stances on many of the issues that have blocked agreement on the details of sinks and other mechanisms, have pursued a unified strategy against the EU in the climate negotiations.

The EU, meanwhile, wants the use of the mechanisms to be kept to a minimum because it fears that excessive use of them would discourage industrialized countries from making sufficient efforts at home to cut greenhouse gases.

Although Japan, Germany and many other industrialized countries — not including the U.S. — want to see the Kyoto Protocol become effective by the 10th anniversary of the Earth Summit in 2002, the collapse of COP6 in The Hague has put reaching that goal in doubt.

The protocol requires ratification by 55 signatory countries to the 1992 U.N. convention on climate change before it can take effect. But only a dozen developing countries have so far ratified the protocol. No industrialized country has ratified the document because of the lack of agreement on the specifics of the sinks, emissions trading and other mechanisms.

The new U.S. administration of President Bush is expected to be much less enthusiastic about COP6 than Clinton's was. Bush has even expressed a skeptical view of the need to get the Kyoto Protocol in place, claiming there is no solid scientific evidence of greenhouse gases causing global warming.

The Republican-dominated U.S. Congress is also opposed to ratifying the protocol before major developing countries, like China and India, make what leading members describe as "meaningful participation" in efforts to cut greenhouse gas emissions.

With only four months left before the planned resumption of COP6 in Bonn, a flurry of environmental diplomacy is expected to be launched by many nations.

Around mid-February, Jan Pronk, the Netherlands' environmental minister and COP6 chairman, is expected to work out amendments to a proposal presented to COP6 in November to try to achieve a breakthrough in negotiations, the sources said. The amendments will be made on the basis of opinions on the original proposal that were submitted by U.N. convention signatory countries to the convention secretariat in Bonn by mid-January, the sources said.

At the end of March in Trieste, Italy, environmental ministers from the Group of Eight major countries will meet, and COP6 will top their agenda. The G8 comprises the U.S., Canada, Britain, Germany, France, Italy, Japan and Russia.

In late April, the Conference on Sustainable Development, a major environmental unit of the U.N., will hold a meeting in New York. Immediately before or after the CSD meeting, the secretariat of the 1992 U.N. convention on climate change is planning to convene a ministerial-level meeting of some 30 major industrialized and developing countries in New York to try and narrow their differences over COP6, the sources said.