The prime minister has said he wants to be honest about the "costs and trade-offs" of tackling climate change.
In a statement on Tuesday, Rishi Sunak said he was proud that "Britain is leading the world on climate change", and will stick by the agreements the UK has made internationally.
But he then overhauled measures designed to meet these targets.
So, is the UK really a world leader on emissions cuts, and how will the changes the PM announced affect its efforts?
How has net zero progress been so far?
Mr Sunak said the government was still "completely committed" to the 2050 net zero target which his predecessor, Theresa May, made law back in 2019.
Net zero means a country does not add any additional greenhouse gases like carbon dioxide to the atmosphere.
"This country is proud to be a world leader in reaching net zero by 2050. But we simply won't achieve it unless we change. We'll now have a more pragmatic, proportionate, and realistic approach that eases the burdens on families," he said.
It is true the UK has been successful in cutting emissions compared to other countries.
Since 1990, emissions within the UK have fallen by 48.7% up to the end of 2022 - excluding international aviation and shipping - according to government data.
These cuts are greater than other countries in the G7 (Group of Seven), an organisation of the world's seven largest so-called "advanced" economies - although Germany has reduced its emissions at a faster rate compared with the UK since 2015.
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But the cuts the UK has made so far are - arguably - the easiest ones.
One of the main ways they have been achieved is by switching away from fossil fuels - coal, oil and gas - to generate electricity.
Emissions from electricity generation have fallen by around three-quarters since 1990, while the proportion of electricity generated by renewables - like wind and solar - has soared.
The government has bold plans to continue this "decarbonisation" process.
But achieving net zero means cutting emissions across all sectors of the economy.
That is why there are targets for phasing out petrol and diesel vehicles and switching from gas boilers to heat pumps or other low-carbon alternatives to heat our homes.
And, despite the UK's achievements on climate so far, there have been a number of warnings that progress is beginning to falter. These came even before today's announcement.
Earlier this year, the Climate Change Committee (CCC) - the government's independent advisers on cutting carbon emissions - warned that the UK's efforts to meet its net zero commitments were already "worryingly slow".
It also said it was "markedly less confident" than a year earlier that it would meet its 2030 and 2035 emissions reduction targets.
Similar warnings on electricity have come from the National Audit Office and a cross-party group of MPs.
But contrary to these findings, Mr Sunak claimed in his announcement that the UK was "on track" to meet its commitments.
He also announced a substantial increase in the subsidies available to people who want to install heat pumps to heat their home, with the grant increased by 50% to £7,500.