The French government officially made its bid for the EU’s banking watchdog in London this week, with President François Hollande declaring Paris’ candidacy for the European Banking Authority in a letter to European Commission President Jean-Claude Juncker.

The bid means the EU27’s two powerhouses are now locked in a battle to host the agency, which must relocate once the U.K. leaves the EU.

“I would like to inform you of the candidacy of Paris to welcome [the EBA to set up] its headquarters,” Hollande said in the letter, seen by POLITICO and dated May 2. “Paris hosts four of the eight largest banks in the EU27 … [and] it’s essential that the EBA is implanted in the heart of the financial ecosystem, allowing for a constant interaction with professionals in the sector.”

France will face down Frankfurt over the EBA. German officials have played up the city’s candidacy for the EBA. The German city is already home to the European Central Bank, its Single Supervisory Mechanism and the European Insurance and Occupational Pensions Authority (EIOPA).

Officials in Frankfurt have even suggested that the banking watchdog could be merged with EIOPA to create a so-called “twin-peaks” model — a move that France opposes. Instead, moving the EBA to Paris would “assure an equilibrium between the setup of regulators within the principal places of European finance, as there is no EU banking institution that has been established in Paris,” Hollande wrote.

“In Paris, the EBA would be able to benefit from the proximity of the European Securities and Markets Authority, which have important synergies … for the quality and coherence of regulation,” he added.

Hollande’s move to grab the EBA comes just weeks after his government said it would launch a bid to bring the European Medicines Agency to Lille.