Tony Blair has called for the government to change course on climate, suggesting a strategy that limits fossil fuels in the short term or encourages people to limit consumption is “doomed to fail”.

In comments that have prompted a backlash within Labour, the former prime minister suggested the UK government should focus less on renewables and more on technological solutions such as carbon capture.

Blair said people were “being asked to make financial sacrifices and changes in lifestyle when they know that their impact on global emissions is minimal”. He said “any strategy based on either ‘phasing out’ fossil fuels in the short term or limiting consumption is a strategy doomed to fail”.

Writing the foreword for a report from the Tony Blair Institute (TBI), he said the current climate debate was “riven with irrationality” and suggested net zero was losing public support.

His comments echo similar criticism of net zero by the Conservative leader, Kemi Badenoch.

The paper itself, written by the TBI’s Lindy Fursman, said net zero policies were now “increasingly viewed as unaffordable, ineffective or politically toxic”.

In the UK, however, climate change policies have retained popularity. The thinktank Persuasion UK said in a report published on Monday that Labour could lose far more seats at the next election from disillusioned leftwing voters defecting to the Greens than from defections to Reform. The most recent YouGov poll on the subject found 66% of UK voters were worried about climate change.

Last week Keir Starmer said the government was going “all-out” for a low-carbon future, telling a conference in London that tackling the climate crisis and bolstering energy security were “in the DNA of my government” and that “we won’t wait – we will accelerate”.

But Blair said present policy solutions were inadequate and leaders should shift towards a “pragmatic policy” that prioritised technological solutions. He said this was borne out by rising demand for production of fossil fuels, especially in China and India, the doubling of airline travel and increased demand for steel and cement.

He said he still believed the climate was “one of the fundamental challenges of our time” and that renewable energy was necessary. But he said the government needed “to alter where we put our focus”.

Fossil fuels are the largest contributor to the climate crisis, accounting for more than 75% of global greenhouse gas emissions.

Blair said there was disdain for policies such as carbon capture in favour of renewables, which he said should be reversed, though the UK government has already made some significant commitments on carbon capture. He called for an international embrace of nuclear power and more work on new small modular reactors.

One Labour MP said it was an unhelpful intervention that could be interpreted as a direct critique of Starmer and his energy secretary, Ed Miliband. “We know that businesses see renewables as a key path to economic growth, and it’s not like the government aren’t already doing things like carbon capture. I don’t get the point of pushing something like this – and the unpopularity of net zero is just plain wrong,” they said.

An industry source said: “I don’t think the sector has any need for a tech-optimist vision of climate action that doesn’t represent the fantastic work the industry is doing today to both decarbonise and roll out clean energy at an unprecedented scale and it seems bizarre that the TBI report doesn’t recognise that.”

The TBI, which has been highly influential in Labour circles, had welcomed action on renewables as recently as February when the seventh carbon budget was published. In a statement published at the time, Fursman said the programme was “rightly ambitious. In order to achieve it, cleaner options like heat pumps and EVs [electric vehicles] must be affordable and accessible”.

Campaigners and industry figures said there were flaws in the TBI argument. Holly Brazier Tope, the deputy director of politics at Green Alliance, said: “This report is disappointing given Tony Blair’s strong track record on climate action, seeming to throw in the towel on avoiding the worst climate impacts and promoting defeatism instead of real solutions. It also wildly exaggerates the public backlash, especially in the UK where support for climate action remains solid.”

Adam Berman, the director of policy and advocacy at Energy UK, said: “Net zero is the economic opportunity of the 21st century. Through the rapid uptake in technologies like wind and solar, UK emissions have halved since 1990. It’s not a question of either or; the UK will need both conventional clean technologies that are operating at scale today in addition to investments in newer technologies.”