AIB has opened a voluntary severance scheme, which could see up to 200 jobs cut.
The scheme is entirely voluntary and limited to a number of areas.
It is believed staff in debt management, homes and consumer units are among those targeted.
The bank says it is as a result of a continuous focus on managing costs and reviewing its resourcing requirements.
It adds that voluntary severance is "one solution" to meet these requirements.
Staff members have until mid-October to apply for the scheme.
A temporary hold on recruitment and promotion is also in place.
Explaining the move, an AIB spokesperson said: "AIB is a large, agile organisation which is focused on being simple and efficient, and this is supported by a continual focus on managing costs.
"In line with this, the bank continuously reviews our resourcing requirements, and VS [voluntary severance] is one solution offered to meet these requirements in certain areas.
"The bank is open to considering VS applications from employees in certain areas of the organisation and we have advised the union of that.
"A temporary hold on recruitment and promotion is in place in line with the bank's renewed focus on cost discipline."
The bank, which has operations across Ireland and the UK, employs almost 10,000 people.