The bank, still reeling from a £290million fine for its part in the Libor rigging controversy, is understood to have taken action against the wheeler dealers after being contacted by regulators.
Royal Bank of Scotland is also believed to have already suspended two traders as part of the investigation.
It came as US banking giants Citigroup and JP Morgan confirmed they were working with regulators as the global probe deepened.
Both Barclays and RBS declined to comment on the suspensions, but have confirmed they have been drawn into the investigations.
give them all a bonus.........