Citigroup Inc. has been ordered to suspend some derivative transactions by the Financial Services Agency, the regulator said Friday.

Citigroup's Japan banking unit also had some of its retail operations suspended, while UBS AG's Japan unit was likewise hit with sanctions.

Part of the New York-based Citigroup's retail business will be suspended for 30 days, the FSA said in a statement. Citigroup's trading unit will be suspended from selling products tied to interest rates for 14 days and its head, Brian McCappin, may resign.