Angela Rayner’s proposed tax raid on savers and high earners would accelerate the exodus of Britain’s wealthy, a leading global wealth adviser has warned.

Rich people will leave the UK in greater numbers if the Deputy Prime Minister succeeds in her efforts to tax wealth more , Henley and Partners said.

Philippe Amarante, the firm’s head of private clients, told The Telegraph: “What I hear from people is their response to this will most likely be ‘I want out’.”

“If a country like the UK continues to make its fiscal balance sheet healthier by taking away from those who have more, those who have more will become fewer. The equation will not work.”

The firm, which has 60 offices globally, is one of the world’s largest investment migration consultants and benefits when the wealthy are on the move.

Last week a leaked memo emerged revealing that Ms Rayner has been pushing for the Chancellor to raise taxes in order to avoid further spending cuts.

The Deputy Prime Minister suggested several measures that would hit well-heeled Britons the hardest, such as equalising levies on dividends and income, and taxing pension pots more.

She also suggested extending the freeze of the £125,140 threshold for additional rate taxpayers, meaning more high earners would be dragged into the 45pc tax bracket.

However, Ms Rayner is playing with fire with such proposals, the wealth manager warned.

Mr Amarante said: “The concern that wealthy people have is about less wealth acceleration and more about wealth preservation. If a government is trying to tax them unreasonably highly, these people will go somewhere else because they can.”

A record 10,800 millionaires left the UK last year amid anger over Labour’s tax policies, previous Henley and Partners analysis suggested – more than twice as many as in 2023.

Several high-profile names are among the latest émigrés, including Nassef Sawiris, Egypt’s richest man and the co-owner of Aston Villa.

They also include the most senior Goldman Sachs banker outside the US, Richard Gnodde, and billionaire property tycoon brothers Ian and Richard Livingstone .

British nationals are already the second-largest group of buyers of real estate in Dubai , one of the most popular destinations for high-net-worth individuals who leave.

The Covid pandemic also prompted greater numbers of wealthy Britons and Americans to seek citizenship in other countries as an “insurance policy” in case of another pandemic or war, according to Mr Amarante.

Mr Amarante said: “If you had asked me two, three or four years ago, I would have said the majority of our clients are those with less powerful passports. But that is not valid any more. One of our largest source markets is actually the US and the UK now.”

He added: “There is an underlying concern – a bit of life insurance policy thinking – that if we get to another crisis of a global scale, pandemic, war, conflict or something else unforeseeable that at least I have the option to react.”

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