The boss of the biggest bank in America again warned that a bad Brexit deal may mean cutting 4,000 jobs from the firm's UK base.
JP Morgan chief executive Jamie Dimon said the bank would have no other option if the UK could not agree seamless financial service trading arrangements with the European Union after Britain leaves the bloc next March.
Dimon told the BBC at the World Economic Forum in Davos: "If we can't find reciprocal recognition of rules - and there are a lot of people who are mad with the Brits for leaving and want their pound of flesh - then it could be bad. It could be more than 4000."
Cut this deep would amount to more than a quarter of the US bank's British presence.
Dimon's comments, at the Swiss ski resort where business and world leaders are gathered this week, mean he has flip-flopped on his view of how much Brexit may hurt Europe's largest financial centre.
Prior to the June 2016 referendum the head of the $402bn-valued bank said up to a quarter of the firm's UK jobs could be axed. But since the vote the bank revised down that estimate to between 500 and 1,000.
JP Morgan agreed to buy a Dublin office block with room for 1,000 staff last May, and in November announced plans to add about 60 new staff in Paris.
Morgan Stanley, Citigroup, Standard Chartered, Nomura Holdings and Sumitomo Mitsui are among those that have already announced plans to move staff Frankfurt.
UK Chancellor Philip Hammond told a Davos audience yesterday (24 January) that Britain would refuse to sign a Brexit trade deal with the EU that did not included financial services.
Any deal that did not include the sector would not be "fair", the Chancellor said.