Rishi Sunak has vowed to scrap hundreds of remaining EU laws and regulations if he triumphs in the Tory leadership race, as Penny Mordaunt faces scrutiny for her views on trans rights.

In a fresh pitch to win over Brexiteers, the former chancellor promised to appoint a Brexit minister to comb through the remaining 2,400 EU laws still on the UK’s statute book.

He even promised a “Big Bang 2.0” for the City thanks to an overhaul of the remaining EU financial services regulations.

It comes as the final five leadership contenders prepare to face off again in the second televised debate on ITV on Sunday evening.

In a statement setting out his proposals, Mr Sunak stressed that he had always backed Brexit, even though he had been warned it could damage his political career, because it was the “right thing” for the country.

Mr Sunak topped the first two rounds of voting by MPs but still remains short of the 120 votes he needs to guarantee him a place in the final two.

As it happened – Saturday’s politics news as Kemi Badenoch opens up big polling lead

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Meanwhile, rival leadership candidate Penny Mordaunt is under scrutiny for her stance on gender self-identification, after leaked government documents suggested she had supported watering down the legal process for transitioning.

Papers apparently drawn up by civil servants and seen by the Sunday Times appear to suggest she favoured removing at least one of the medical requirements.

A spokesperson for her campaign hit back: “The fact that so much of this contest has been distracted by side issues instead of the cost of living crisis impacting millions of people, is a major disappointment.

“Arguing about policy is one thing, but questioning Penny’s values and integrity must be challenged.

“To be clear, on the issue of self ID, leaked documents prove that all ministers in the department wanted to maintain medical involvement, including Penny. Other ministers can back this up.”

The former defence minister also faces questions about allegedly accepting £20,000 from a trustee of a climate-sceptic lobby group.

Ms Mordaunt reportedly took two £10,000 donations from a business run by tycoon Terence Mordaunt, a trustee of the Global Warming Policy Foundation, the Sunday People reports.

In what has surely been a trying few days for Ms Mordaunt since the first TV debate, she has also seen her polling lead among Conservative members vanish.

A new poll of Tory party members by ConservativeHome has Kemi Badenoch ahead with 31% of those polled, with a commanding leader over second-placed Liz Truss on 20%.

Then comes Ms Mordaunt on 18%, who has dropped from first place, followed by former chancellor Rishi Sunak and Tom Tugendhat.

Away from the leadership contest, cabinet minister Alok Sharma has threatened to quit if the next prime minister does not commit to a strong net zero agenda.

Mr Sharma, who led last year’s landmark Cop26 UN climate summit, told The Observer that while it was “absolutely a leadership issue”, some of the remaining candidates in the Tory leadership race had been only “lukewarm”.