The Brexit fallout continues, with concerns rising that Visa might move hundreds of jobs out of the UK, the London Stock Exchange's merger with Deutsche Bourse could be hampered, and the City's role running euro clearing is under threat.
As the financial services sector scrambles to digest the implications of last week's referendum result, which saw the British people vote to leave the European Union, jobs and business are at risk.
According to Sky News, Visa may relocate hundreds of positions to the continent because of a clause in the recent multi-billion dollar acquisition of Visa Europe, which insists that transaction data does not leave Europe.
Citing sources, Sky says that German regulators are likely to push for Visa's UK-based data centre operations to be moved to an EU country.
A Visa spokesperson told Sky: "While we continue to monitor the situation carefully, it is premature to speculate on whether possible changes to the location of our data centres would make sense or be required."
Several big banks - including Citi and Goldman Sachs - have already warned that they will move jobs to other EU cities if the UK does not get access to the single market's passporting regime.
Another potential Brexit casualty is the plan for a London headquartered post-merger LSE-Deutsche Bourse. Felix Hufeld, boss of German regulator Bafin, says that "it is hard to imagine that the most important exchange venue in the eurozone would be steered from a headquarters outside the EU...There certainly has to be an adjustment here."
Hufeld also says that euro-based trading could go through Frankfurt, which could also soon be home to the European Banking Authority, which will have to move its base from London because of Brexit.
French President Francois Hollande has also stepped into the euro clearing debate, saying: "The City, which could handle clearing operations in euros thanks to the UK’s presence in the EU, won’t be able to do them any more."
Last year the European Central Bank lost a court case that tried to bring clearing under its regulatory control by shifting it from London to a euro-area country. However, the Brexit vote may change the landscape.
Industry veteran Hirander Misra has told Bloomberg: "Clearing is very much cross border and also depends on confidence in the clearinghouse. That said, there’s nothing stopping EU authorities from putting in pseudo barriers to entry."