Merrill Lynch has sent emails to all its employees asking them to consider voluntary redundancy.
The investment bank has messaged just under 70,000 people across 44 countries.
It affects everyone from secretaries to analysts and brokers.
The US company is offering between 12 and 54 weeks' salary, dependent on length of service, and staff have been given a few weeks to decide whether to accept.
The bank is said to be looking to cut jobs as part of a group-wide overhaul.
It has refused to discuss numbers, although press reports have put the figure at around 10,000.
Earlier this year, Merrill reported a 41 per cent collapse in second-quarter profits after being hit by global stock market volatility.
This is the first time it has offered voluntary redundancy to all staff. A Merrill spokesman refused to comment.
PA