The WWF believe by removing appliances and their energy use from the definition the initiative can no longer be defined as “zero carbon”.

The federation said the change announced in the Budget effectively transfers the task of providing clean energy for these homes from the housebuilder to the wider power sector.

It said: “This fundamental shift in policy will result in new homes being built that add to the overall emissions burden of UK homes.

“The zero carbon homes policy, as it stood, would have been a pioneering policy instrument for the UK, putting us not only ahead of European housing policy, but in the lead globally too.

“The last four years had seen a real change across industry and supply chains with house builders and suppliers gearing up to deliver this policy from 2016.

“Many companies were gearing up their supply chains in the expectation of tough housing standards and the demand that the ZCH policy would create for community renewable projects.

“The decision has undermined their progress, and sends the worst possible signal to companies that have planned their investments on the basis of the original zero carbon homes policy.”

Colin Butfield, Head of Campaigns at WWF-UK, said: “Since 2007, WWF has been dedicated to working with the Zero Carbon Taskforce on a pioneering piece of housing policy.

“So it is a shattering blow to find out, without consultation, that the Government has taken a decision to undermine both climate and housing legislation. WWF is left with no choice but to resign from the taskforce as the ‘zero carbon’ homes policy comes tumbling down.”