Bloomberg reported that JPMorgan Chase & Co. plans to move hundreds of London-based bankers to expanded offices in Dublin, Frankfurt and Luxembourg to preserve easy access to the European Union’s single market after Brexit,  according to the firm’s head of investment banking  Daniel Pinto.

Pinto, in an interview in Riyadh, told Bloomberg, “We are going to use the three banks we already have in Europe as the anchors for our operations.  We will have to move hundreds of people in the short term to be ready for day one when negotiations finish, and then we will look at the longer-term numbers.”

Global banks are preparing to move some London-based operations into new or expanded bases inside the EU after British Prime Minister Theresa May began the formal process for quitting the 28-nation bloc. Before last year’s referendum, JPMorgan Chief Executive Officer Jamie Dimon told U.K. employees that as many as 4,000 could be relocated in the event of Brexit. In January, he said that number could be higher—or lower—depending on how the government’s negotiations played out.

“We have to plan for a scenario where there is no U.K.-EU passporting deal, and we have to move a substantial portion of our business to continue serving our European clients,” Pinto said. “We’ll have to wait to see what kind of deal can be achieved and see what we need to do from there.”