Nomura’s investment banking business outside its core markets helped to deliver the most profitable quarter in six years at the Japanese bank’s wholesale unit.

The wholesale unit, which houses the bank's sales and trading and traditional investment banking businesses, made almost twice as much profit in the first three months of 2015 - Nomura's fiscal fourth quarter - as in the previous nine months, according to the Japanese bank's quarterly and full-year results published on Thursday morning. The growth was driven by a rebound in fixed income sales and trading outside Asia and the best quarter for international investment banking since 2010.