more: The removal of a reference in the MEF draft to halving emissions by 2050 is a blow to efforts to secure a new U.N. climate pact in December.

MEF nations account for 80 per cent of world greenhouse gas emissions, largely caused by burning fossil fuels.

Last year the G8 outlined a "vision" of halving emissions by 2050, without setting a base year. Major developing countries did not sign up for a 2050 goal, arguing the rich first had to set deep cuts in their own national emissions by 2020.

A draft G8 statement seen by Reuters today agreed the rise on global temperatures should not exceed 2 degrees Celsius. That would mark a breakthrough by EU states in convincing the United States, Japan, Russia and Canada that a 2 degrees Celsius (3.6 degrees Fahrenheit) limit is the necessary threshold beyond which climate change will reach danger levels.

G8 leaders meet later today.