The Committee on Climate Change (CCC) has launched a stinging criticism of the government’s continued failure to publish its Clean Growth Plan.

The independent advisory body to the government on climate issues this morning published its annual report, analysing the progress already made towards the country’s 2050 emissions reduction target under the Climate Change Act.

However the CCC has been far from favourable in its review, condemning the government for a series of delays to the publication of both the Clean Growth Plan and National Adaptation Programme.

The fifth carbon budget, for the period 2028 – 2032, was agreed by then-energy secretary Amber Rudd in July last year and now, almost a year later, the government is yet to announce legislation for how it will meet associated targets.

The CCC acknowledged that political upheaval has beset plans, but has not held back in its criticism of the delays. In comparison, the CCC noted that plans to meet the fourth carbon budget were set just six months after the budget was legislated.

Earlier this week new climate change minister Claire Perry said it was her intention to publish the plan after parliament returns from summer recess in September. Such a deadline would mean the plan’s publication was more than nine months late.

“It is nearly a year since the fifth carbon budget was set. Many existing policies are running out and additional new policies are required. Parliament must now be informed about how the agreed targets will be met.

“The longer time required to date in part reflects wider events. However, it is now neither justified nor wise to delay any further the publication of the plan that is required by law,” the report states.

The CCC has therefore called for the “urgent” publication of the CGP, which it says must include effective new strategies and policies.

Of crucial importance to the power sector is how the government intends to source the 80 – 100TWh of low carbon electricity which will be needed by 2030, a figure which already takes into account any expected generation from Hinkley Point C and offshore wind generation contracted under the current Contracts for Difference mechanism.

That need is set against a backdrop of curtailed development of onshore wind and solar – the two cheapest forms of low carbon generation – and continued uncertainty regarding the future of the Levy Control Framework.

Greater concern was raised over the lack of decarbonisation occurring in the transport and built environment sectors, with emissions from buildings actually increasing in the time since the last carbon plan was put into place.

Lord Deben, chairman of the CCC, warned that progress on climate issues would stall without urgent further action.

“New plans, for a new Parliament, are needed as a matter of urgency to meet our legal commitments, grasp the opportunities offered by the global low-carbon transition, and protect people, businesses and the environment from the impacts of a changing climate.”

Friends of the Earth’s Simon Bullock echoed Lord Deben’s consternation.

“This is the starkest warning yet from the climate committee that the UK government must up its game. The committee reported last year that progress is stalling and UK climate targets are now off track – but this has not been acted upon.

“Climate change threatens the security of everyone at home and abroad and the continual delay from ministers on producing a fit-for-purpose strategy is simply unacceptable,” he said.

Richard Black, director at think tank the Energy and Climate Intelligence Unit, said it was now clear that the UK government had been “treading water” on climate issues.

“Unless ministers get on with setting new decarbonisation policies for the power sector, heating and transport, progress will stall and the UK will lose its leadership position.

“Investors are ready and willing to put money into Britain’s low-carbon future – they just need clear, unequivocal signals from government. And given the economic benefits of decarbonisation, one might ask – what are ministers waiting for?” Black said.