The G8 of Germany, France, Italy, Japan, Canada, Russia, the USA, and the UK, together with Brazil, China, India, Mexico and South Africa have reached a tentative agreement to at least halve global CO2 emissions by 2050.

The deal came at the latest G8 Summit, in Heiligendamm, Germany, with the big emerging economies also incorporated in the process, and includes the worlds biggest greenhouse gas emitters, the United States, China and India.

Details of how this goal is to be achieved will be thrashed out as part of a post-Kyoto Protocol regulation “based on differentiated responsibilities” and to be adopted by 2009 and agreed at the United Nations Framework Convention on Climate Change (UNFCCC) conference in Indonesia.

The group is to “consider seriously” decisions made by the European Union, Canada and Japan which include at least a halving of global emissions by 2050. The non-binding agreement will see the G8 countries share energy technology with the emerging economies, while financial tools such as emissions trading, the Clean Development Mechanism (CDM), or tax incentives will support climate protection projects in developing countries. Key goals of the new framework are to rapidly accelerate commercialisation of emerging low carbon technologies, promote sustainable development and energy security while significantly cutting global greenhouse gas emissions.

The breakthrough deal includes developing nations on the back of a US insistence to include the major energy consuming and greenhouse gas emitting economies of the world in addressing technology, energy efficiency and market mechanisms to avert climate change.

Nonetheless, chairing the Summit, German Chancellor Angela Merkel, said that “industrialised countries must take the first step.” Merkel added that binding goals on reducing emissions were also necessary as “an important signal.”

The agreement, endorsed by George W Bush, came just days after the US president highlighted his country’s efforts to expand the use of “clean, safe nuclear power” as part of a programme to make advanced energy technology commercially viable in order to cut carbon emissions.