JP Morgan CEO Jamie Dimon has cautioned the United Kingdom's new Prime Minister, Andy Burnham, against implementing tax increases on the financial sector, warning that such moves could drive businesses out of the country and jeopardize the bank's planned £3 billion London headquarters.

Dimon stated that higher taxes could have "adverse consequences" for investment in the UK, suggesting that a tax raid on banks would be "one more negative on that bucket of things you got to think about." He noted that increased taxes on banks, such as a higher bank levy or corporation tax surcharge, could lead to capital flight.

"If you have an uncompetitive tax system, capital leaves your country," Dimon said, referencing the trend of companies delisting from the London stock market. "And if capital leaves your country, it goes to other countries."

Dimon reiterated previous warnings that JP Morgan might reconsider its plans for a new London HQ, a project expected to house 12,000 employees and cost £3 billion, if the government adopts policies hostile to banks. He urged caution for any government considering penalizing companies.

Burnham replaced Sir Keir Starmer as Prime Minister on Monday, and his administration is reportedly considering new policies that may necessitate tax increases to fund spending. While former Chancellor Rachel Reeves resisted calls for a bank levy, a more left-leaning cabinet under Burnham might be more receptive to such measures.

Analysis by City broker Peel Hunt indicates a significant trend of London-listed firms facing takeover bids, with the value of these bids far exceeding the value of new company floats in the first half of the year. This broader market trend adds to concerns about the UK's financial competitiveness.