The British government has been accused of trying to “fiddle” the country’s climate change targets after cabinet ministers agreed to carry forward past “overperformance” in emissions reductions to allow a potential breach of pollution limits in coming years.  The news comes as the UK is preparing to adopt one of the most ambitious long term carbon targets in the world of net zero emissions by 2050 and as London lobbies to host the UN climate talks in 2020.  Ministers decided over the weekend to use past overperformance in emissions reductions by all sectors of the economy to relax the agreed limits up to 2027, ignoring a warning from the government’s climate advisory group.

John Gummer, Lord Deben, the chair of the Committee on Climate Change, wrote to ministers in February urging them not to take advantage of the existing rule that allows the target to be changed in such circumstances.  But cabinet ministers are proceeding with the maneuver after Philip Hammond, the chancellor, wrote last week to colleagues urging them to reject the CCC’s advice for the first time since it was set up a decade ago. His proposal has been adopted by Greg Clark, business secretary, whose department is responsible for the policy. Under Britain’s plans to reduce carbon from the atmosphere and tackle climate change, the government has committed to a series of five-year “carbon budgets” that restrict emissions to a certain level.

During the second carbon budget, from 2013 to 2017, Britain emitted 384 megatonnes (million tonnes) of carbon dioxide below its cap of 2,782 megatonnes. Mr Hammond requested that 88 megatonnes of carbon pollution be carried forward to allow the UK to breach the limit in a future carbon budget. One ally said the chancellor saw the move as an “insurance policy” for the next government, given the regular “flux” in carbon emissions depending on economic growth.

By contrast, the government canceled the surplus from the first carbon budget that ran from 2008 to2012).  The UK is already off track, in terms of meeting its carbon budget for the next period of 2023 –  2027, according to government projections.

“It is basically saying, ‘let’s slow down on this transition’. And that will make it more difficult for us to make our end goal, the net-zero goal,” said Mike Childs, head of science, policy and research at environmental group Friends of the Earth. “It is not illegal, but it is definitely fiddling with the carbon budget.”