(Bloomberg) -- Liz Truss vowed to scrap all remaining EU laws by the end of 2023 if she becomes prime minister, as she vies for votes with Rishi Sunak in their battle to win the Conservative Party leadership election and succeed Boris Johnson.

European Union rules “hinder” British businesses, Truss said in a statement late on Friday, as she promised to set a sunset deadline or every piece of EU-derived regulation. That includes scrapping the Solvency II rules governing insurers that critics say are too onerous, curtailing their ability to invest in long-term assets such as infrastructure.

The Foreign Secretary’s promise matches one made last week by Sunak, who wrote in the Telegraph that he’d task a new Brexit delivery department with reviewing the remaining 2,400 EU laws on the British statute book with a view to scrapping or reforming them all by the next general election, due in January 2025 at the latest.

Brexit is shaping up to be a key battleground in the race to become the next prime minister. While Truss campaigned for remain in the 2016 referendum, she’s embraced the divorce with the zeal of the convert and burnished her credentials by introducing a bill designed to scrap large parts of the Brexit deal governing Northern Ireland. That helped secure the backing of the European Research Group of Brexit-backing Conservative MPs. 

That Truss is more trusted within the Tories to deliver on Brexit is frustrating for Sunak, who campaigned and voted for the UK to leave the bloc. 

The former chancellor on Saturday will turn to another crisis facing Johnson’s successor: the backlogs in the National Health Service that have left 6.6 million people waiting for cancer screenings, surgery and consultations. Sunak will announce plans on his first day in office to create a task force focused on reducing waiting times, aiming to get the number of people waiting for appointments falling by next year and one-year waits eliminated by September 2024.

In an interview with the Times, which has declared that Sunak is “the right and responsible choice,” he identified five national crises and pledged to put the country on an emergency footing on the first day of his premiership.

Sunak and Truss now face six weeks of hustings around the country to win over the votes of the about 175,000 Tory Party members who will choose between them. The new Prime Minister is elected September 5.

EU Ramps Up Legal Pressure on UK Over Breaches of Brexit Deal

Tensions between the UK and EU over Brexit escalated on Friday after the bloc launched four more infringement proceedings against Britain, claiming the government has failed to comply with customs and value added tax rules it signed up to. Truss’s bill to override parts of the agreement was approved by the House of Commons without amendments earlier this week, and now heads to the House of Lords for debate in the fall.

How to manage the tricky relationship with the EU -- and whether to resume Brexit negotiations -- will be a significant test for Johnson’s successor. On Thursday, the Treasury said in a statement that the cost of the UK’s divorce bill had jumped to £42.5 billion ($51.1 billion) from a previous estimate of £35 billion to £39 billion.

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