British property owners will no longer have to pay more for environmental upgrades if they carry out a loft or garage conversion.

At the start of this year it was announced that proposals were in the pipeline which would see homeowners spend ten per cent of the value of extension work on energy-efficient improvements to their property.

However, the Conservative Party appears to have turned its back on the plans, with a source close to David Cameron telling the Daily Mail that they "should never have been in consultation".

A government source said: "The idea that people are going to be forced to improve their energy efficiency or install a new boiler because they want to extend their garage or make their house better is not going to happen."

They added that the prime minister is opposed to it and the proposal will not become policy.

"It is not fair to ordinary people trying to improve their homes," the source added.