FACTBOX - What was agreed in Marrakesh?
The accord, reached after tough bargaining at a two-week U.N.-sponsored conference in Morocco, provides a detailed rulebook governing the complex 1997 treaty aimed at limiting humanity's negative impact on the Earth's climate.
WHAT WAS AGREED IN MARRAKESH?
The rules cover issues such as what penalties countries that fail to reach their targets will face, how they can buy and sell the right to emit greenhouse gases, and to what extent countries must report on the amount of emissions they produce each year.
Supporters of the pact say this provides the detailed legal basis for countries to ratify it and bring it into force.
BUT WASN'T ALL THIS AGREED IN THE SUMMER?
The main points of the rulebook were agreed at a similar meeting in Bonn, Germany, in July. But that was a relatively brief political agreement.
WHY DID IT TAKE TWO WEEKS TO REACH THE MARRAKESH DEAL?
Translating the Bonn agreement into legal text opened up long-standing differences between countries and what was meant to be a purely administrative exercise turned political.
WAS THE TREATY GIVEN LEGALLY BINDING SANCTIONS?
The Bonn agreement set out the sanctions a country would face if it failed to meet its emissions targets - that country would have to make up the shortfall at a penalty rate of 130 percent, provide an action plan showing how it intended to cut emissions and would be barred from emissions trading.
Wrangling at Marrakesh centred on whether this would be legally binding. Japan and Russia resisted moves to make it so.
A compromise wording was found which postponed a formal decision on the exact legal nature of compliance, but stated that countries must accept the agreed compliance rules if they want to take part in emissions trading.
WHAT ABOUT THE ISSUE OF "SINKS"?
Carbon sinks - trees and agricultural land that can store carbon which might otherwise be emitted into the air - have caused major upsets at all recent climate negotiations.
Despite initial opposition by the EU, the deal gives countries the right to discount some of their emissions target by counting the carbon stored in managed forests and farmlands.
Each country is given a maximum amount of emissions it could count in its "carbon sinks". The main beneficiaries are Canada, Japan and Russia.
Marrakesh also sets the rules making countries define and annually report on their sinks activities.
DOES THIS MEAN THE KYOTO PROTOCOL IS NOW UP AND RUNNING?
Kyoto will only come into legal force when it is ratified by the governments of at least 55 countries representing 55 percent of 1990 CO2 emissions. The EU has said it will do so next year. Without the United States - which pulled out of Kyoto in March - it is critical that Russia and Japan ratify to make up the numbers. If they do not, Kyoto will collapse.