The heir to JCB’s vast manufacturing empire has warned Rachel Reeves’s Inheritance Tax (IT) policy could force the UK-based business to move to America. From April, only the first £2.5m of a business’s assets is eligible for tax relief after the owner’s death; the rest is taxed at 20%.

But JCB chairman Lord Bamford's son, Jo, says Britain risks losing one of its major success stories to the US due to the US's more favourable tax rates. He said the family tax is a "real problem" and that the Staffordshire-based firm could "quite easily become an American business”.

He told The Telegraph: "I love being in Britain.

“I love being here. I love our factories. But I would say to a political party of any stripe, there’s only so much you can ultimately do.”

A Treasury spokesperson said: “We’ve listened and raised the relief threshold to £2.5m to protect more small family businesses, while ensuring the largest make a fair contribution so we can deliver support for families and businesses, including cutting the cost of living.”

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