Prime minister Boris Johnson has announced that the UK will cut greenhouse gases “faster than any major economy”, with a pledge to cut annual emissions by at least 68% compared with 1990 levels by 2030. The previous aim was to hit a 57% reduction by 2030.

The move comes ahead of a virtual international climate summit that will be hosted by Johnson next week.

“Today, we are taking the lead with an ambitious new target to reduce our emissions by 2030, faster than any major economy… But this is a global effort, which is why the UK is urging world leaders as part of next week’s Climate Ambition Summit to bring forward their own ambitious plans to cut emissions and set net-zero targets.”

Yet despite increasing the UK’s climate ambitions, Johnson did not offer any clues as to how this goal would be achieved.

For well over a year, the British government has been promising to publish an Energy White Paper that will set out its plans and policies to hit net-zero emissions by 2050 — a target enshrined in UK law. It was initially due to be released by the end of 2019, but has repeatedly been pushed back, and is now said to be coming this month.

“It is clear there is now a yawning gap between the government’s aspirations and its policies to deliver them,” said former energy secretary Ed Miliband, who is now the shadow business secretary. “The government didn’t have the policies to meet their previous target, and the chasm will be even greater now.”

Ed Matthew, COP26 director for the Climate Coalition, which comprises 140 civil society groups, added: “This is important progress but not sufficient. A more ambitious cut is both feasible and necessary to keep us safe, and reflect our massive historic carbon emissions.

“We must remember, too, that the climate will not respond to targets, it will respond to carbon cuts. It is action that counts.”

Business groups also called on the government to unveil more details about its plans.

“While [the 2030 target] undoubtedly represents a real stretch, there is no doubt that business is up for the challenge as we build back better and greener following the pandemic,” said Rain Newton-Smith, chief economist at the Confederation of British Industry. “Publishing the energy white paper as soon as possible, and moving with speed, determination and greater ambition to deliver the policies in the government’s ten-point plan, is essential to our success.”

Johnson unveiled a long-trailed ‘ten-point plan’ for the green economy last month, which promised to mobilise £12bn ($16bn) of government investment, and up to £36bn from private sources, behind marquee pledges such as ending the sale of new petrol and diesel cars by 2030 and heating a whole town with hydrogen by the same date.