A UN climate conference with nearly 200 countries has adopted an extension of the Kyoto Protocol through 2020.
The 1997 pact, aimed at controlling the greenhouse gas emissions of major industrial countries, expires this year.
Negotiators haggled through the night in Doha to finalize details of a deal that will mean Kyoto continues for another commitment period.
However, the second phase only covers about 15 per cent of global emissions after Canada, Japan, New Zealand and Russia opted out.
The U.S. never joined Kyoto, partly because it didn't include China and other fast-growing developing countries. Canada formally withdrew from the accord a year ago.
Countries aim to adopt in 2015 a wider treaty that would apply to all countries and enter force when the Kyoto extension expires.
Delegates also agreed to postpone until next year discussions on demands from developing nations for more cash to help them cope with the rising costs of mitigating disasters blamed on global warming.