However, when asked by Times Radio if the timing of the ban was immovable Michael Gove, the British housing secretary, on Tuesday replied “yes”.

Asked later by Sky News if that was an “absolute guarantee,” Gove again replied: “Yes.” 

Sunak has faced increased pressure from members of his own Conservative Party to water down his pledges geared toward eliminating the UK’s net carbon emissions by 2050 in the wake of a special election last week in which the Tories unexpectedly eked a narrow victory over Labour after campaigning against local restrictions on vehicle emissions.

The 2030 ban — as well as a generous government subsidy — formed the backdrop of Indian conglomerate Tata Group’s decision to plough £4bn into a new electric car battery plant in the UK last week.

The government is trying to encourage more companies to build so-called “gigafactories” in the UK.

The Tata Group is the parent company of the British car maker Jaguar.

While the government might be sticking to that timeframe, Mr Gove did suggest they may review the pace of its rollout of low-carbon domestic heating systems, such as heat pumps, in lieu of gas boilers. He said they did not want people paying "excessive sums" during a cost of living crisis. 

Asked about a policy to require all new homes to use such systems from 2025, Gove told Times Radio that is one area “I do think that we need to review again”, while stressing that new housing “should meet net zero standards”.

The government’s 2025 mandate on heating systems for new homes aims to help grow the market in heat pumps to some 600,000 installations a year by 2028. The government also aims for new heating systems installed in all homes to be low carbon from 2035 — or in the case of gas boilers, capable of at least being converted to use hydrogen.

• Bloomberg