They are hatching a plan to ensure that London banks and the financial services sector are allowed to continue to trade as before, fearing any attempt to thwart transactions would have a negative impact on the remaining 27 states.
The European Parliament’s committee on economic and monetary affairs says their own negotiators should tread carefully as they bash out deals.
In a sign that negotiations could well turn positive for Britain and the EU, the report instructs negotiators to look at trying to get a “workable” deal in order to offset uncertainty.
The report adds: “If financial services companies choose to leave the UK as a result of Brexit, the consequences should be carefully evaluated.
Now commentators say the revelation is good news for the UK economy after months of speculation over the potential of a “cliff edge”.
Anthony Belchambers, chairman of the Honorary Advisory Council of the Financial Services Negotiation Forum said chickens are coming home to roost.
“They recognise a drawbridge between the EU and the UK would hurt both sides.”
UK government lawyers are already looking at replicating passporting rules which would allow them to trade as normal.
Mr Hammond confirmed he had been notified by major Japanese banks, who employ 5,000 people in Britain, that they are looking to parachute out of the UK.
He said: “It’s fairly binary for them: they either have access to their markets or they don’t have access.
“If they don’t, they will have to restructure the way their operations address the European market.”
However the UK could effectively replicate EU rules in order that the financial services sector could continue to keep their interests in Britain.
But as the EU demands a £60bn pay off from Britain to effectively move the process along, it has been claimed banks are getting set to move out en masse as the EU refuses to clarify whether they will be giving passporting rights.