US president Barak Obama, UK prime minister David Cameron, German chancellor Angela Merkel and the heads of France, Japan, Canada and Italy called for the 'decarbonisation' of the world economy by 2050.
In a communique published on 8 June, the G7 leaders reaffirmed their commitment to the Copenhagen Accord, which will involve investing $100 billion a year by 2020 in "meaningful mitigation actions", and to the elimination of inefficient fossil fuel subsidies.
Climate change can only be met by a global response, the communique said. The leaders committed to working with all parties to the UN Framework Convention on Climate Change (UNFCC) to reach "the upper end" of the latest IPCC recommendation of 40 to 70 % reductions by 2050 compared to 2010.
Key strategies mentioned in the communique include: the development and use of innovative technologies in the energy sector; development of long term national low-carbon strategies; incorporation of climate mitigation and resilience considerations into development assistance and investment decisions; support for vulnerable countries' own efforts to manage climate change related risk; and phasing down use of hydroflurocarbons (HFCs).
However, the group did not commit to any immediate targets for reduced emissions. The communique said that specific targets will be set at the COP21 Climate Change Conference in Paris in December 2015 and that the G7 remained determined to adopt a protocol, another legal instrument or an agreed outcome with legal force under the United Nations Framework Convention on Climate Change (UNFCCC) applicable to all parties.
Six of the seven G7 members have submitted greenhouse gas emission targets to the UNFCCC. The EU has committed to a binding target of an at least 40% domestic reduction of greenhouse gas emissions by 2030 compared to 1990, to be fulfilled jointly, while the US "intends to achieve" a reduction of 26-28% below its 2005 level by 2025. Canada's target is a reduction of 30% below 2005 levels by 2030.
Georgie Messent, environment law expert at Pinsent Masons, the law firm behind Out-Law.com, said: "Key countries in the G7, particularly the US, have failed to show any real commitment to key measures to avoid or minimise climate change, like international carbon trading. I hope that this isn't just more empty rhetoric."
"Genuine commitment from the G7 could trigger renewed support for nuclear power to provide baseload electricity, introduction of responsible shale gas projects and additional investment in renewables. There is however a balance to be struck, as fossil fuels will inevitably remain part of the energy mix for some time to come," Messent said.
"Removal of fossil fuel subsidies could have a significant impact on oil and gas companies. We know that international resources companies involved in upstream oil and gas are now actively reconsidering their strategies with respect to renewable energy and looking to negotiate the political and regulatory minefields in this area," she said.