Bank of England Governor Mark Carney and other top officials from the central bank spoke to reporters on Thursday after the BoE published its Financial Stability Report which looks at risks to the economy from the financial sector.
Threadneedle Street said the City of London was well prepared to withstand the shock of Britain crashing out without a deal at the end of October without failing as they did in the financial crisis.
That convention has come under strain in recent years from developing economies demanding a greater say at the Washington-based institutions, although the American David Malpass was elected unopposed in April to head the World Bank.
"Share trading obligation would be one example where European actions have the potential to create some disruption that could have knock on effects".
Lagarde is leaving the International Monetary Fund two years ahead of schedule after European Union leaders, at a summit this month, nominated her to succeed Mario Draghi as ECB president. "There's a process to confirm [Lagarde at the European Central Bank] and then there's a process to select her successor".
Nonetheless, "material risks of economic disruption remain" beyond Brexit concerns, with the ongoing US-China trade war and the global slowdown in economic growth, the report said.
"Fundamentally there's issues around any money laundering and counter-terrorism financing". "It's got to be rock solid from the start or it's not going to start".
"Well-managed firms are expected to lead the transition and re-negotiate their contracts to refer to alternative reference rates well in advance of the end of 2021".
The U.K. has long relied on foreign investors to finance its yawning current-account deficit, which, at 5.6% of national income in the first quarter, is the widest among comparable major economies.
"What's crucial is that first and foremost is that we maintain the elements that make the United Kingdom such an attractive place for investment".
The new report comes just a day after analysis from the Department for the Economy warned that a no-deal Brexit could risk 40,000 jobs in the north, result in the crash of cross-border agri-food trade and a slump in investment from foreign companies.