Canada's ratification of the 1997 Kyoto Protocol on Climate Change brings the treaty's total membership to 100 and it now requires only Russia's seal of approval to enter into force early in 2003.
"Achieving the symbolic threshold of 100 ratifications demonstrates that the Kyoto Protocol has widespread international support," said Ms Joke Waller-Hunter, executive secretary of the UN Framework Convention on Climate Change, under which the protocol was adopted.
But she warned that the industrialised countries have only 10 more years to meet their Kyoto targets to reduce greenhouse gas emissions - "and the evidence today is that most of them still have a great deal of work to do".
Ms Waller-Hunter also pointed to the large number of developing countries that had ratified the treaty, saying this was "a sign of their commitment to the protocol as an instrument of global co-operation to address a global problem".
The Kyoto Protocol requires a "double trigger" for entry into force. The first trigger is ratification by 55 governments - a requirement that was met earlier this year. The second trigger is that the ratifying governments must include industrialised countries representing at least 55 per cent of that group's 1990 carbon dioxide emissions.
With the receipt of Canada's ratification, and that of Poland on December 13th, industrialised country ratifications now account for 43.7 per cent of 1990 CO2 emissions (as determined in 1997 when the protocol was adopted). Russia's 17.4 per cent will be essential for pushing the tally over the required 55 per cent limit.
Japan and the EU have already ratified. Besides Russia, ratification is also pending in about a half dozen, mostly smaller, industrialised countries which would not in themselves take it above the 55 per cent threshold. Australia and the US have stated they will not join the protocol.
The protocol commits developed countries to reducing their collective emissions of six key greenhouse gases by 2008-12. The individual targets include 8 per cent for the EU.
Under an EU "burden-sharing" arrangement, Ireland is obliged to cap its emissions at 13 per cent above 1990 levels by 2010.
