Net zero targets will force Britons to change how they live their lives, the Labour chairman of Parliament's energy committee has said.
Bill Esterson, the most senior backbencher charged with scrutinising the Government's energy policy, said ordinary people will "absolutely" have to adjust their habits if it is to meet the UK's ambitious emissions goals for 2030.
His remarks directly contradict Sir Keir Starmer's claim earlier this month that the Government can hit its climate targets without telling people "how to behave."
It comes after the head of the independent climate change committee warned households will need to switch out gas boilers for heat pumps and use more electric cars to meet the UK's new net zero goals.
Labour has made one of its five missions to transition to clean power by 2030 through a de-carbonisation of the electricity grid.
It is part of a wider push towards net zero, which includes a commitment to reduce carbon emissions by 68 per cent of 1990 levels by 2030.
At the Cop29 climate summit in Baku on Nov 12, Sir Keir outlined a new target to cut emissions by 81 per cent by 2035.
He told the conference he would not tell Britons "how to behave" or tell people "how to live their lives".
But speaking at The New Statesman's Politics Live Conference last week, Mr Esterson said people would "absolutely" be required to make adjustments as part of the transition to clean energy.
Asked if people would be "forced to change their lives" to hit the 2030 targets, he said: "Clearly whenever there is a big change, people have to change their lives. So absolutely, yes."
Mr Esterson told The Telegraph he believes "we will all have to change our lives because the world is changing, just as we always have".
"This time the changes are in response to climate change and the transition to net zero," he added.
A No 10 source rejected Mr Esterson's comments, standing by Sir Keir's remarks in Baku.
Emma Pinchbeck, the head of the climate change committee, has also warned that the green power grid would be insufficient to meet the Government's 2035 emissions target, resulting in a need for people to switch gas boilers for heat pumps and use electric cars.
The goal is referred to as a nationally determined contribution within the UN climate process, and is a stop on the way to its overall target of net zero by 2050.
All countries will have to produce a new target next year as part of the UN process, but the UK has moved early as Sir Keir seeks to promote the country as a climate leader in the face of growing scepticism within Europe and from the incoming Trump administration.
The mounting claims that everyday adjustments will be needed in the transition to clean energy threatens to undermine the Prime Minister's assertion that Labour can wean Britain off fossil fuels without requiring ordinary people to make sacrifices.
Asked at Cop29 if it would really be possible to hit his 2035 emissions target without making changes to everyday life, he said: "Yes, of course it is and the target is my target and the plan is my plan. I am not borrowing from somebody else's plan."
"The target is as set out today. I don't think that as we tackle this really important issue the way to do it is to tell people how to run their lives and instruct them how to behave and I am not going to do that."
On Friday, Claire Coutinho, the shadow energy secretary, wrote to her counterpart Ed Miliband demanding "full transparency" over the cost of the 2030 clean power target.
"The British public deserve to have a fair assessment of what the costs of different approaches may mean for their lives and livelihoods," she said.
"On an issue of such importance, I am sure you will agree that the public would expect nothing less than full transparency."