After drawing international acclaim, Indonesia's moratorium on forest clearing has proved hard to implement, as special interests whittle down the area protected under the agreement, environmental groups say.

China's civil aviation authority on Wednesday reiterated its opposition to the European Union's imposition of an emissions trading scheme on global aviation, despite a threat from the EU last week to punish Chinese airlines for not cooperating.

As talks have so far proven futile, the parties involved expect that a framework of market-based measures, which will be submitted next year to the International Civil Aviation Organization Assembly for review, might put an end to disputes over the issue.

Australia's Bureau of Meteorology said the climate models it monitors indicate a possible return of the El Nino weather pattern, often linked to heavy rainfall and droughts, in the second half of 2012.

The last severe El Nino in 1998 killed more than 2,000 people and caused billions of dollars in damage to crops, infrastructure and mines in Australia and other parts of Asia.

Britain's climate policies can help shield the economy from oil and gas price shocks triggered by external factors such as the Arab Spring, an analysis commissioned by the government showed on Friday.

Energy price spikes can often dent economic growth, business investment and employment, as witnessed during the global financial crisis in mid-2008 when oil rose to nearly $150 (95 pounds) per barrel, research group Oxford Economics said in a report.