Sunak takes a sleeper train to Cornwall for the election campaign

Mr Sunak said he was “absolutely committed” to leveling up in Cornwall.

It follows a report which said Tory plans to launch national services for 18-year-olds could starve Cornwall of money for community safety and high street regeneration.

Areas including Merthyr Tydfil in South Wales, Cornwall and the Tees Valley are among the areas with the most to lose, according to research by the Institute for Fiscal Studies (IFS).

The plan to close the government’s Shared Prosperity Fund (UKSPF) by 2028 and use £1.5 billion to support military and volunteering opportunities for 18-year-olds could see richer areas in the south of England to receive “a substantial increase in net funding,” the researchers found.

According to the IFS, UKSPF is worth £145 per person in Cornwall and the Isles of Scilly, rising to £246 in Blaenau Gwent in South Wales and £273 in Merthyr Tydfil.