JPMorgan Chase has put its chief currency dealer in London, Richard Usher, on leave, a source familiar with the matter said on Wednesday, and Bloomberg reported Citigroup had done the same with its chief dealer.
This mirrors developments at Standard Chartered, which has also put one of its senior forex traders on leave, according to a source familiar with the matter. Matt Gardiner joined StanChart from Swiss bank UBS only last month.
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JPMorgan is one of several banks cooperating with the Financial Conduct Authority in Britain and other regulators around the world looking into allegations of currency manipulation in the $5.3 trillion-a-day global market.
It was unclear whether JPMorgan's decision to put Usher on leave had anything to do with this investigation.
However, Bloomberg reported that both Usher and Citi's Rohan Ramchandani went on leave after regulators probing forex manipulation started investigating traders' use of an instant-message group.
Ramchandani, Citigroup's head of European spot trading, was told on Wednesday he would be placed on leave, Bloomberg said, quoting someone with knowledge of the matter.
Ramchandani was a member of chat rooms that are a subject of the probes, the Wall Street Journal reported, quoting people with knowledge of the matter. The probes are continuing but no wrongdoing by Ramchandani had been discovered, it said.
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Usher, head of spot G-10 currency trading, joined JPMorgan from Royal Bank of Scotland in May 2010. He remains a full-time employee at JPMorgan and has not been suspended. But he hasn't been at his desk for around two weeks, the source said.
Usher could not be reached for comment, and JPMorgan and Citigroup declined to comment.
Usher is still listed as "active" on the U.K. Financial Conduct Authority's register, and is listed as one of the 13 members of the Bank of England's Joint Standing Committee's chief dealers group at the end of last year.
The Bank of England declined to comment, however, on whether he was still on that committee.
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Royal Bank of Scotland said on Wednesday it had sought to reassure clients about the foreign exchange rates they were being offered and rival Barclays said it was cooperating with regulators scrutinizing the market.