Some 950 Ulster Bank workers are facing redundancy by the end of the year in a second swathe of massive job cuts which trade unions branded as breathtaking.
No branches are expected to close but 600 employees in the Republic of Ireland and 350 in Northern Ireland will be battling for their future.
Larry Broderick, general secretary of the Irish Bank Officials Association, said the impact of the latest round of cuts could be even more severe than the 1,000 lay-offs in 2009.
"The sheer magnitude of this second wave of proposed redundancies is breathtaking," he said.
Ulster Bank, a subsidiary of the Royal Bank of Scotland (RBS) which on Thursday announced a separate 3,500 job cuts in its investment wing, claimed it was taking the drastic action to remain competitive. Branches are not expected to be closed, it added.
Arlene Foster, Northern Ireland Enterprise Minister, said such a significant number of job losses is very worrying. She said: "With front line staff facing redundancies, it is important that senior management in RBS are seen to be behaving in a responsible manner as the organisation moves forward."
Mr Broderick said he will be seeking clarification from Ulster Bank's parent, RBS, on its commitment to Ireland.
"Our members feel very strongly that Ulster Bank staff are continuing to suffer for the mismanagement, incompetence and greed of senior management in Ulster Bank's parent company, RBS, which has been nationalised in all but name, as a result of the biggest collapse in British corporate history," Mr Broderick said.
RBS has been refinanced with £45.5 billion of British taxpayers' money and is more than 80% state-owned.
Ulster Bank, although a major player and loser in the Irish property boom and bust over the last decade, is not part of the Irish Government's bank bailout scheme or the bad-bank recovery plan through the National Asset Management Agency (Nama).
© 2012 Press Association