ACCBank is to quit the Irish market with the loss of about 180 jobs.
The Irish subsidiary of Dutch banking giant Rabobank said that next year it will close all its branches and business centres to the public and give up its banking licence.
It posted losses of more than 200 million euro (£170.5 million) for last year.
Kevin Knightly, the bank's country manager, said ACCBank has suffered significantly due to the deterioration of the Irish property market over the last five years.
"While costs have been cut significantly, including a substantial restructuring programme in 2009, we are heading towards a situation where, without intervention, our costs will exceed our income during 2014," he said.
"This is an unsustainable position and we need to take action now."
ACCBank said it will focus solely on debt recovery and all funds on deposit with the bank will be repaid in full to customers.
The closure will see 180 voluntary redundancies out of a workforce of 470.
ACCBank, an agri-lending bank, said it will continue to be a regulated entity and will support its customers in the farming sector. It is looking into outsourcing a small portion of its loan book that does not include its agri-business.
Rabobank said the closure would not impact its separate business in Ireland.
Mr Knightly added: "ACCBank has remained at the forefront of loan recovery activity in the Irish market. We will continue with our approach to loan recovery but do not need to be a fully licensed bank for this purpose."
ACCBank was set up in the 1920s to provide an avenue for farmers to get access to credit, and quickly became known as the farmers' bank.
Its business changed dramatically after being bought out by Rabobank just over a decade ago and it started lending for property development and speculation.
Trade union leaders at Unite and Sitpu claimed the bank should never have been privatised just over a decade ago and should have stuck to its core mission of supporting the farming business.
The bank management held talks with unions last night and confirmed that 10% of the loan book would be outsourced and jobs will go over the next 18 months.
In a joint statement, Unite's Colm Quinlan and Siptu's Adrian Kane said: "The sale of ACC to Rabobank unfortunately saw it entering the property market and the ultimate folly of this decision is being paid by the workforce today with the announcement that 180 jobs are to go in 2014."
ACCBank was a state-controlled bank until Rabobank stepped in. Its investment has soured in the downturn and it has been forced to pump in about 1 billion euro (£852.4 million) to shore up its books and provisions for bad loans are up to 1.2 billion euro (£1.02 billion).
Tom Doyle, the chair of the Irish Farmers' Association (IFA) farm business committee, said farmers are concerned about their business but that assurances have been given that all farmer-related term loans will be serviced and that new loans will be offered to farmer customers.