The politics of global warming: Is it nyet or not on Kyoto accord?

When does "nyet" really mean "nyet"? That question hangs like the sword of Damocles over international climate talks in Milan, Italy, this week and next.

Over the past few days, Russian officials in Moscow have issued conflicting statements about their country's intention to ratify the 1997 Kyoto Protocol - a pact many see as a critical first step to combat global warming.

Even as the pact's opponents issued statements congratulating Russian President Vladimir Putin for pounding the last nail into the agreement's diplomatic coffin, several analysts urged caution.

They acknowledge that Russia may yet officially reject the Kyoto accord, but add the current statements leave too much wiggle room to read as the final word.

"Many people have wanted to declare Kyoto dead," says Elliot Diringer, director of international strategies at the Pew Center on Global Climate Change. "But it's not yet time to perform the last rites."

Under the 1997 agreement, industrial countries are required to reduce emissions of heat-trapping carbon dioxide by an average of 5 percent below 1990 levels during a five-year period beginning in 2008. But under the protocol's ratification formula and with the United States out of the process, the pact can't enter into force if Russia balks.

The volleys began Tuesday, when Mr. Putin's top economic adviser told reporters in Moscow that because of the country's need for economic development, Russia cannot ratify the pact "in its current form." By Wednesday, other Russian officials in Washington and Moscow said Andrei Illarionov was speaking for himself, not for Putin. Thursday, Mr. Illarionov shot back that his stance came from the Russian president himself.

Meanwhile, researchers again warn that human activities have already affected the climate in irreversible ways. Writing in Friday's edition of the journal Science, two leading researchers say that based on the best available evidence, "modern climate change is dominated by human influences, which are now large enough to exceed the bounds of natural variability."

"We are at a critical stage in the international climate effort. Kyoto's entry into force would be a major achievement, but only a start. On the other hand, if Kyoto doesn't get off the ground, the international community must begin thinking right away about the alternatives," said Pew Center President Eileen Claussen in a statement Thursday.

To longtime Russia hands, the back-and-forth has a familiar ring. "For the Russians," says one former US diplomat, "what's mine is mine, and what's yours is negotiable." Russian officials have also been known to provoke a crisis at the opening of talks "to wring concessions on provisions others thought were settled long ago."

The mixed statements also reflect a continuing debate over the economic implications of the Kyoto Protocol for Russia, observers say. Exports of oil and gas are fueling the country's economic growth. But the protocol is designed to wean the world away from fossil fuels.

Under the protocol, a country whose emissions are likely to fall below its target can sell credits to other countries. Because Russia's economy has been in such rocky shape, it would be the single largest source of these credits. And until President Bush withdrew from Kyoto, the US would have been the biggest buyer.

Once Bush backed out, "the big bonanza that was to come to Russia disappeared," says John Reilly, an economist with the Massachusetts Institute of Technology. He estimates the annual value of Russia's credits dropped from at least $10 billion a year to between $100 million and $200 million. "My sense is that Russia is bargaining to try to get something more from Europe or from other Kyoto parties before it ratifies," he says.

Russia may also be trying to hold Kyoto hostage to unrelated diplomatic goals, analysts add. In early November, Russia and the European Union held a summit aimed at allowing Russia to join the World Trade Organization. But Europe has balked, in part because it sees Russia's low domestic natural-gas prices as a hidden subsidy.

Russia may be signaling to Europe that it would be more likely to give its nod to Kyoto if the EU backed off on demands for Russia to boost energy prices internally.

To proponents of the protocol, Russia still stands to gain. Under a Kyoto program called "joint implementation," countries can earn credits against their emissions targets by investing in energy-efficient projects in Russia and former East bloc countries Given that many Russian factories still rely on technologies from the 1930s, these projects could help Russia meet its goals for economic development.

The key question is whether Russian officials see it the same way.