Ed Miliband had Labour MPs laughing in their seats as he brutally mocked his Tory shadow.
The energy secretary told Claire Coutinho “the job of opposition is to oppose the government, not yourself” after she criticised Labour’s carbon emissions targets.
Miliband told her the Conservatives - who only left office after 14 years in July - had backed the same targets.
“She is now opposing the very same target that her government put into law and she claimed that she was working towards as secretary of state just a few months ago,” he said.
“There is a pattern here. Every week, the right honourable lady takes to Twitter to express her latest outrage about a policy, asking who on earth could support this.
“And every week, someone pops up in her replies and says quite rightly ‘you did, just a few months ago’.
“Because this isn’t the only one. Last week, she came out against the clean heat market mechanism - another policy she proposed. In fact, I have a statement from her from only eight months ago when she said it would be coming in in April 2025, which is exactly what this government is doing.
“The truth is, any passing bandwagon she will leap on it, even if it means trashing her record.”
As Labour MPs on the government benches laughed, Miliband added: “Let me give her a little advice about opposition. The job of opposition is to oppose government, not oppose yourself. And this is where she has ended up.”