Sir James Dyson, the billionaire inventor of high-tech vacuum cleaners, has become an outspoken critic in recent weeks of Britain’s plan to reintroduce inheritance tax for farms. He should know: his farming empire alone could result in about ￡122mn in death duties.

The entrepreneur — who sparked controversy by supporting Brexit then moving his eponymous technology company’s headquarters from Wiltshire to low-tax Singapore in 2019 — has developed one of the UK’s largest farming businesses, owning some of the country’s most productive agricultural areas.

The 77-year-old tycoon — who says he has a mission to “protect and nurture” British farmland — has been able to expand his agricultural business over the past decade free of the threat of death duties. The company says it has invested a total of ￡140mn to upgrade its farms.