The first departure out of Canary Wharf following the vote to leave the EU may soon be under way.

The European Banking Authority has 159 people working in One Canada Square – but the European Union has said it is preparing the ground to shift to another city.

Catch up on all the Brexit news

Paris and Frankfurt are vying to take over the role, with Ireland also making a late bid, although it may be the the unit is collapsed altogether. This is because the Single Supervisory Mechanism, based at the European Central Bank and focusing on the eurozone could absorb the role. It makes Frankfurt the stand-out contender as the EBA’s new base.

The EBA writes and co-ordinates banking rules across the EU, including for stress tests, and would stay in place until there were concrete alternative arrangements. EBA chairman Andrea Enria said before the vote the authority would have to be based in an EU country.

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The SSM, however, is a later addition to the institutions and has the whip hand on the effort to form a banking union and the move towards an all-encompassing eurozone.

The EBA covered euro and non-euro countries, accounting for 29% of the EU’s GDP. This reduces to 11% without Britain and the non-euro countries although all, but Denmark, have pledged to join the single currency.

The future of the European Medicines Agency, which has just opened a skyscraper on the estate, is also in doubt .