The comments come after the CEO of Goldman Sachs International, Richard Gnodde, told CNBC in March that it would be shifting jobs from London and bulking its European presence by "hundreds of people." However, the bank also confirmed at the time that this movement away from London would not necessarily result in a net reduction of workers in the U.K.
Relocation destinations are thought to include Dublin and Frankfurt, though Blankfein said he hoped the bank would not have to trigger plans.
Blankfein said negotiations between the EU and the U.K. would need to include an implementation period of "a couple of years" to ensure that the financial services industry can continue to operate once negotiations conclude in early 2019.
"We are talking about the long-term stability of huge economies with hundreds of millions of people and livelihoods at stake and huge gross domestic product," he told the BBC.
"So, if it takes a little while - I'd rather get it right than do things quickly."
Read the full story on the BBC's website here.
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