The worldwide boss of JP Morgan has said othat the Wall Street bank would only have to move thousands of jobs out of the UK in response to Brexit if ordered to do so by the EU.

In the run-up to last year’s referendum, Jamie Dimon had warned that up to 4,000 roles would be at risk in the event of a vote to leave.

Speaking at a conference in Paris on Tuesday, Dimon said the initial response would require several hundred jobs to go – but the final number would depend on the demands imposed by the EU’s regulators and politicians.

Some 16,000 staff are employed by JP Morgan in the UK – including 4,000 in Bournemouth – and around 75% of the business they conduct is for EU companies, Dimon said.

Dimon said JP Morgan had to be ready for hard Brexit – whether it was likely to happen or not. “It’s easy we plan for that ... all it means is that several hundred jobs have to legally be done through an EU sub[sidiary],” he added.

He said JP Morgan could handle most of its activities this through its existing operations in the EU in Dublin, Frankfurt and Luxembourg.

The bank is buying a landmark office block in Dublin that could house 1,000 staff, double its current workforce in the Irish capital.

Dimon said: “People should focus more on the second step ... What happens next is totally up to the EU. It’s not up to Britain.

“If the EU determines over time that they want to move a lot more jobs out of London into the EU, they can simply dictate that. The regulators can dictate it, the politicians can dictate it,” he said.

“If regulators say one day ‘we’re not comfortable with your risk people, your lawyers, your compliance being in the UK,’ they can make us move it. ”

Dimon was speaking on a panel alongside Stuart Gulliver, the chief executive of HSBC, who confirmed the bank’s plan to move 1,000 roles to Paris – out of 43,000 – in the event of a hard Brexit.

The conference – in which Paris is making a pitch for financial services business – is being held just days before the Bank of England’s deadline for hundreds of banks and fund management firms to submit plans for how they would cope with a hard Brexit.