CIBC is not alone in being caught out when the coronavirus outbreak interrupted gold supply routes and gold futures prices in New York shot above London spot prices.

HSBC said earlier this month it suffered paper losses of about $200 million on one day in March.

The losses by both banks are theoretical, reflecting the value of positions they held. They would become real only if the bank exited the positions when their value was low.

CIBC said the loss happened on March 24 and was “mostly attributable to our precious metals trading business.”

It was by far the biggest trading loss of any day since May last year, its report showed. CIBC said it was mostly recouped in April.

Gold trading banks plan to reduce their gold futures positions significantly on CME Group’s Comex exchange in New York because they fear further price volatility, Reuters reported on Thursday.

A reduction of activity by banks on Comex, the world’s largest gold futures market, would increase the relative importance of London as a trading centre and raise costs for thousands of gold investors who use the exchange.