G7 leaders said at a summit Monday that deep cuts in global greenhouse gas emissions are required with a "decarbonisation of the global economy" over the course of this century.

Ahead of a UN climate summit in Paris late this year, the Group of Seven big industrialised nations called for global emissions cuts of 40-70 percent by the middle of the century compared to 2010 levels.

The G7 also reaffirmed the goal of limiting global warming this century to two degrees Celsius (3.6 degrees Fahrenheit) from pre-industrial levels, first agreed at a 2009 UN climate summit in Copenhagen.

Scientists warn that on current trends, Earth is on track for double that target.

"Urgent and concrete action is needed to address climate change," they said in a final statement after a two-day summit in Germany.

"We emphasise that deep cuts in global greenhouse gas emissions are required with a decarbonisation of the global economy over the course of this century."

The goal in cutting heat-trapping greenhouse gases is to slow global warming which is blamed for melting the planet's ice caps and glaciers, raising sea levels and causing more violent storms, floods and droughts.

The Group of Seven leading industrialised countries -- Britain, Canada, France, Germany, Italy, Japan and the United States -- make up about 10 percent of the world population but one quarter of global emissions.

Not at the G7 summit were China, the world's number one polluter, and other big emerging economies such as India, Russia and Brazil.

The G7 also said they were committed to jointly mobilise financing from public and private sources for a previously agreed 100-billion-dollar fund to finance climate efforts in poor countries from 2020.