A former Tory minister has quit the party while praising Sir Keir Starmer’s “competent political leadership”.

Claire Perry O’Neill, a former energy minister, referred to the Conservatives as her “former party” in a piece for The Times in which she heralded Labour’s approach to overhauling the country’s energy system.

She said the Conservative Party — which she joined in 2006 — had become “dominated now by ideology and self-obsession”.

The once-senior Tory does not appear to have defected, with the article saying she is “no longer a member of any political party”.

An MP for nine years, Mrs Perry O’Neill served as energy minister in Theresa May’s government for two years, with the position upgraded to a cabinet-attending post in January 2018.

She stood down as an MP at the 2019 general election but had been expected to lead Britain’s preparations for the Cop26 climate summit in Glasgow, which was initially planned for November 2020.

Despite being tasked with heading the UK’s efforts by Boris Johnson on his arrival in No 10, she was sacked in February 2020 and replaced by Alok Sharma.

Mrs Perry O’Neill told The Times she had quit the Conservative Party “earlier this month”.

“As much as I like and admire the Prime Minister and Chancellor, they are too beholden to a party dominated now by ideology and self-obsession to deliver the big changes we need in a fact-based, competent way,” she added.

In her article about the approach to reforming Britain’s energy make-up, the ex-Devizes MP said: “My former party’s often cavalier approach to business and academia coupled with a post-Brexit reluctance to strategically engage with our European neighbours has damaged our ability to deliver the energy system we need.”

She said she wanted to “applaud” Sir Keir’s Labour Party for putting “energy at the top of their proposed new government inbox”.

The former politician highlighted Labour’s “industrial support for key green technologies” and a “national low-carbon wealth fund”, labelling the ideas “exciting”.

She added: “Building a low-carbon, secure, affordable energy system for the UK is an immense challenge that needs sober, fact-driven, competent political leadership.

“I sense that is exactly what we will get should Labour win the next general election.”