JPMorgan Chase CEO Jamie Dimon met UK Prime Minister Andy Burnham at Downing Street on Wednesday, amid growing concerns that the upcoming Budget could introduce a windfall tax on banks. Dimon, who also met with Chancellor John Healey, has previously criticized such a move, warning of "adverse consequences" for the economy. JPMorgan employs 23,000 people in the UK, with major operations in London and Bournemouth, and is building a £3bn headquarters in Canary Wharf.

Dimon is among several banking leaders who successfully dissuaded former Chancellor Rachel Reeves from raising bank taxes last November. However, Healey now faces pressure to find new revenue sources ahead of his first Budget on October 28. Trade unions and some MPs argue that highly profitable banks should be taxed more to help households with the cost of living. One senior City executive noted the proposal has "superficial attraction" but would be "self-harming" for the government.

HSBC, Barclays, Lloyds Banking Group, and NatWest have generated over £200bn in pre-tax profits in the past five years, largely due to higher interest rates. UK banks already pay a 28% corporation tax rate, above the standard 25%, plus an additional surcharge. Dimon said in July that further tax increases would be "one more negative" for the sector. Healey has not ruled out higher bank taxes but declined to comment on speculation, emphasizing the importance of banks to economic growth.

The prime minister's office confirmed the meeting but did not disclose details. A Number 10 official said Burnham "dropped into" the talks with Dimon and business adviser Varun Chandra. Healey has pledged to pursue a deregulation agenda for the City, moving beyond the post-financial-crisis focus on risk. Meanwhile, hedge fund billionaire Chris Rokos is relocating from the UK to Greece, citing tax concerns, after earning £477m last year, highlighting the broader issue of wealthy individuals leaving Britain.