The news comes a day after chief executive, Stephen Hester, announced he is stepping down from his job at the bank later this year.
The job cuts will be spread worldwide as the 81%-publicly-owned bank is looking to restructure its investment banking business ahead of its reprivatisation.
The job cuts represent just under one-fifth of the employees in the division, totalling more than 11,000.
Last month, RBS announced it was cutting a further 1,400 jobs at its retail banking head office, adding to more than 35,000 redundancies already unveiled since the banking crisis.
