Analysts expect the firm to reduce its investment banker numbers by around 6,500 worldwide - with some trading desks in the financial centres of London and New York to disappear entirely.
The move would follow new Citi chief executive Vikram Pandit's warning, made earlier this year, that the company needed to "get fit" in the wake of the financial hit of the credit crunch.
Citi has announced asset writedowns exceeding $15 billion so far in 2008.
Elsewhere, Goldman Sachs is also expected to reduce staff numbers - with a ten per cent cut of its mergers and acquisitions unit.
These job losses will come in addition to those enforced following the bank's annual staff review, which saw the worst-performing five per cent asked to leave.
Second quarter profits at Goldman stood at over $2 billion, it was announced last week.