Japan's Mitsubishi UFJ Securities Holdings has warned of huge potential losses over transactions between its subsidiary in London and an unnamed US client.
Losses are also likely at leading Japanese brokerage Nomura Holdings, as well as Switzerland's banking giant Credit Suisse, all involving the same US firm.
Mitsubishi officials said on Tuesday they're evaluating the extent of the potential losses and the impact it could have on the subsidiary's financial results.
Their estimate of the losses as of Monday was 300 million dollars. They say the actual figure could be different, "depending on unwinding of the transactions and market price fluctuations."
In a related move, Japan Exchange Group CEO Kiyota Akira said on Tuesday that he had asked Nomura's top executive to provide relevant information as it becomes available.
Nomura is trying to minimize its losses by asking its client to pay about 2 billion dollars. Nomura has also withheld the client's name and details of the transactions.