A taskforce to speed up home insulation and boiler upgrades has been disbanded according to reports.

The group - which included the chair of the National Infrastructure Commission Sir John Armitt and other leading experts - was only launched in March.

But it appears to be a casualty of Rishi Sunak's decision to scrap energy efficiency regulations for landlords in an overhaul of green policies.

The UK is often described as having some of Europe's oldest and least energy-efficient housing.

Members were informed in a letter, seen by the BBC, that it was being wound up.

Energy efficiency minister Lord Callanan told the group its work would be "streamlined" into ongoing government activity.

Energy analyst Jess Ralston at non-profit group the Energy and Climate Intelligence Unit told the BBC: "This appears to be yet another U-turn that could lead to higher bills just like the prime minister's decision last week to roll back landlord insulation standards that could leave renters paying an additional £8bn on energy bills."

According to the BBC 12 million UK homes were rated D or below on their Energy Performance Certificates, which means they do not meet long-term energy efficiency targets.

This year a BBC investigation found six out of 10 recently inspected UK rental homes failed to meet a proposed new standard for energy efficiency.

Mr Sunak "doesn't give a damn about the climate crisis"

The taskforce's membership included Sir John Armitt; head of leading housebuilder Barratt Developments, David Thomas; and leading experts from the University of Salford, the UK Green Building Council and National Energy Action.

Lord Callanan wrote to members of the group on Friday saying co-chair Dame Alison Rose would not be replaced and the group would be dissolved.

The minister said the ideas and discussions that had come from the group had been "hugely valuable in supporting the ambition to reduce total UK energy demand by 15% from 2021 levels by 2030."

He adds that the work to date had not been "wasted" and that "draft recommendations will be instrumental in driving forward this important agenda."

A spokesperson for the Energy Security and Net Zero department said: "We would like to thank the Energy Efficiency Taskforce for its work in supporting our ambition to reduce total UK energy demand by 15% from 2021 levels by 2030.

"We have invested £6.6bn in energy efficiency upgrades this Parliament and will continue to support families in making their homes more efficient, helping them to cut bills while also achieving net zero in a pragmatic, proportionate and realistic way."

Energy analyst Jess Ralston told the BBC that the "gas boiler and petrol car phase-out weren't set to have any impact on cost of living for struggling families for more than a decade".

"Insulation programmes could have a more immediate impact, yet the prime minister ditched that policy last week and now the government seems to be turning its back on experts and ideas that could help boost energy efficiency," she said.

She added: "Is the government giving up on energy efficiency and those living in leaky homes unable to make the improvements that would keep them warmer?

"Experts like Citizen's Advice are clear if you want to bring down bills you do energy efficiency, you help people to stop wasting heat through rooves, windows and walls."

The group also said the government "could have easily replaced Alison Rose, there are lots of business people who feel they have a stake in how homes can be improved."

Mr Sunak's decision to water down some commitments, while retaining the overall aim of decarbonising the UK economy to "net zero" was welcomed by many in his party.

The PM insisted he was being "pragmatic" and that moving too fast on green policies would "risk losing the consent of the British people".

But Labour's shadow net zero secretary Ed Miliband said the change of direction showed Mr Sunak "doesn't give a damn about the climate crisis".