Speaking before a hearing of the treasury select committee of the House of Commons on Tuesday, Flint said the lender needs to taken preemptive actions to ensure it has enough capacity to deliver its services.
He said HSBC has a full-service bank in France, and in the event it loses passporting rights to provide certain financial services in the European Union as a result of Brexit, it would move activities to "France, or indeed to Ireland or Holland or any other place within Europe" where it has operations.
Flint said that Paris is the likely destination of operations that might be moved. It had been earlier reported that HSBC might move about 1,000 jobs to the French capital.
Flint urged British lawmakers to take a firmer stance in the Brexit negotiations to avoid thousands of jobs being moved away from London.
Banks with large-scale operations in London are reportedly lobbying European officials against a so-called "hard Brexit" as it could possibly harm both the European Union and Britain.
They warned that they might start moving staff out of London in the next few months if Brexit uncertainties are not cleared up.