A UN climate conference with nearly 200 countries has adopted an extension of the Kyoto Protocol through to 2020.
The 1997 pact, which controls the greenhouse gas emissions of rich countries, expires this year.
Negotiators haggled through the night in Doha to finalise details of a deal that allowed Kyoto to live on for another commitment period.
However, the second phase only covers about 15% of global emissions after Canada, Japan, New Zealand and Russia opted out.
The US never joined Kyoto, partly because it did not include China and other fast-growing developing countries.
Countries aim to adopt in 2015 a wider treaty that would apply to all countries and enter force when the Kyoto extension expires.