The Tory peer says the government’s climate change “apathy” makes his environment minister role “untenable”.
Lord Zac Goldsmith has resigned as a minister, after being accused of undermining a Commons investigation into Boris Johnson.
He was among 10 Tories the Privileges Committee said was part of a campaign to interfere with their inquiry.
Lord Goldsmith said the government’s “apathy” on climate change made it “untenable” for him to remain minister for the international environment.
He claimed Prime Minister Rishi Sunak was “uninterested” in the environment.
Lord Goldsmith was the only serving minister to be criticised by the cross-party committee for attacking its work.
In his resignation letter, he said he had been “horrified” at the government abandoning its environmental commitments and withdrawing its leadership on the world stage.
He cited a flagship animal welfare bill being ditched, as well as an abandoned pledge to spend £11.6bn of UK aid on climate and environment.
“The problem is not that the government is hostile to the environment, it is that you, our prime minister, are simply uninterested,” he wrote.
“That signal, or lack of it, has trickled down through Whitehall and caused a kind of paralysis.”