Rishi Sunak was criticised after attempting to mock Sir Keir Starmer’s stance on “defining a woman” after the Commons had heard the mother of murdered transgender teenager Brianna Ghey was watching from the gallery.

The Labour leader condemned the Prime Minister’s remark, with a chorus of opposition backbenchers calling out: “Shame.”

The exchange took place during the Prime Minister’s Questions in the House of Commons, as the leaders clashed over the Government missing targets to reduce NHS waiting lists.

Sir Keir said: “He says he stands by his commitments. He once insisted if he missed his promises, these are the words he used: ‘I am the Prime Minister,’ and then he said: ‘It is on me personally.’

“Today, we learn from his own officials that he is the blocker to any deal to end the doctors’ strikes and every time he is asked, he blames everyone else.

“So, what exactly did he mean when he said it is on him personally if he doesn’t meet his promise?”

Mr Sunak replied: “We are bringing the waiting lists down for the longest waiters and making progress, but it is a bit rich to hear about promises from someone who has broken every single promise he was elected on.

“I think I have counted almost 30 in the last year. Pensions, planning, peerages, public sector pay, tuition fees, childcare, second referendums, defining a woman – although in fairness, that was only 99% of a U-turn.

“The list goes on, but the theme is the same: it is empty words, broken promises and absolutely no plan.”

Sir Keir hit back, saying: “Of all the weeks to say that, when Brianna’s mother is in this chamber. Shame.

“Parading as a man of integrity when he’s got absolutely no responsibility.”

The Labour leader added: “I think the role of the Prime Minister is to ensure that every single citizen in this country feels safe and respected, it’s a shame that the Prime Minister doesn’t share that.”

Sir Keir had opened the session by telling MPs: “This week the unwavering bravery of Brianna Ghey’s mother Esther has touched us all. As a father, I can’t even imagine the pain that she is going through and I am glad that she is with us in the gallery here today.”

Mr Sunak was later asked to apologise to Brianna’s mother for his “insensitive comment”.

Labour MP Liz Twist (Blaydon) said: “May I take the opportunity to ask the Prime Minister if he would consider apologising to Brianna Ghey’s mother for his insensitive comment?”

Mr Sunak did not directly respond to Ms Twist’s request.

Concluding Prime Minister’s Questions, Mr Sunak said: “If I could just say also to Brianna Ghey’s mother who is here, as I said earlier this week, what happened was an unspeakable and shocking tragedy.

“As I said earlier this week, in the face of that, for her mother to demonstrate the compassion and empathy that she did last weekend, I thought demonstrated the very best of humanity in the face of seeing the very worst of humanity.

“She deserves all our admiration and praise for that.”