Jason Clatworthy, a tax partner at Alvarez & Marsal, said more private equity managers had been making enquiries about whether Labour could backdate some of the proposed tax changes.

PE managers setting up new funds were thinking twice about basing themselves in London he said, and many executives had stepped up plans to buy property abroad.

“There’s a swell of people who are consistently saying ‘I’m ready to go if this goes the wrong way and they double my tax rate,” he said.  

“They feel unsettled in terms of the new Government’s approach to taxing people. That has picked up after the election. The lens has definitely been turned.”

Italy, Spain, Portugal and Switzerland have all been flagged as key beneficiaries if Labour pushes through the changes. Italy, in particular, has an appealing tax regime as many private equity managers can qualify for a flat annual tax of €100,000 regardless of income.

Marco Ceretti, a partner at tax firm Maisto e Associati in Milan, said there was increasing demand from London.

He said: “We’ve noticed an increase in people from London since January looking to relocate to Italy for tax purposes and that increase has gone faster since March, which coincided with the announcement by the previous government to repeal non-dom rules and a more concrete chance of Labour winning.

“Some funds have also opened a branch in Italy due to the different tax regimes.”