Rishi Sunak is considering weakening some of the government's key green commitments in a major policy shift.
It could include delaying a ban on the sales of new petrol and diesel cars and phasing out gas boilers, the BBC reports.
The PM is preparing to set out the changes in a speech in the coming days.
Responding to the reported plans, he said the government was committed to reaching net zero carbon emissions by 2050 but in a "more proportionate way".
The aim of net zero is for the UK to take out of the atmosphere as many greenhouse gas emissions - such as carbon dioxide - as it puts in.
The prime minister said: "For too many years politicians in governments of all stripes have not been honest about costs and trade-offs. Instead they have taken the easy way out, saying we can have it all.
"This realism doesn't mean losing our ambition or abandoning our commitments. Far from it.
"I am proud that Britain is leading the world on climate change."
He said the UK was committed to international climate agreements it had already made.
"No leak will stop me beginning the process of telling the country how and why we need to change," he said.
Mr Sunak added that he would give a speech later this week "to set out an important long-term decision we need to make so our country becomes the place I know we all want it to be for our children".
Here's what else is happening in politics today:
Scottish
Parliament
Today’s
business includes:
- Portfolio
Questions: Constitution, External Affairs and Culture; Justice and Home Affairs
- Scottish
Labour Party Debate: Restoring Scotland’s Nature
- Scottish
Labour Party Debate: Protecting Specialist Neonatal Services in Lanarkshire
- Decision Time
- Members’
Business: S6M-10307 Maternity Services in Scotland (in the name of Meghan
Gallacher)
The following
Committees are meeting this morning:
- Education,
Children and Young People Committee
- Rural Affairs
and Islands Committee
- Citizen
Participation and Public Petitions Committee
- Economy and
Fair Work Committee
- Criminal
Justice Committee
UK
Parliament
Today’s
business includes:
- Oral Questions
(Lords): Discussions with the Railway Group and train operators about proposed
station ticket office closures
- Oral Questions
(Lords): Assisting British farmers to meet net zero challenges
- Debates
(Lords): The European Affairs Committee report: ‘The future UK-EU Relationship’
- Environment
and Climate Change Committee – Oral evidence session on Electric Vehicles
Aberdeenshire
Council
Today’s
business includes:
- North East
Scotland Agriculture Advisory Group
Aberdeen City Council
No scheduled
business