Up to 1,800 jobs could be set to go at the troubled Ulster Bank over four years along with around 40 branch closures under plans to return it to profit.
Ulster Bank said the reduction in its workforce took account of the 950 redundancies already announced in January 2012, and it hoped the remaining role reduction could be met through staff turnover.
Royal Bank of Scotland's troubled arm will slash its branch network from 214 to between 175 and 185 by the end of 2014, mainly impacting rural branches as it looks to focus on towns and cities.
It's not yet clear how many jobs are set to go in Northern Ireland or how many branch closures will be based in the region.
In a presentation to investors, it said the turnaround plans would "significantly" reduce its workforce, from around 5,800 full-time staff to between 4,000 and 4,500 by 2016.
Ulster Bank, which has branches across Northern Ireland and the Republic of Ireland, said it was too early to confirm where the job cuts will have an impact.
A spokesman for the bank said it after its initial announcement to reduce staff numbers by 950, Tuesday's proposed further reduction could be met "through natural attrition over the remaining course of the strategic plan".
Irish finance union IBOA said the branch cuts were a "bolt from the blue" and slammed Ulster Bank for its "cavalier" approach to staff and customers.
IBOA general secretary Larry Broderick said: "While everyone is aware that Ulster Bank's parent, RBS, is in some disarray at the moment and its commitment to its Irish operation has been the subject of much speculation recently, I sometimes wonder if the senior management in Ulster Bank are deliberately trying to sabotage the bank's future by their cavalier approach to their customers and staff."
There has been speculation that Chancellor George Osborne was considering jettisoning loss-making Ulster Bank from RBS to help ready the 81%-state-owned group for a return to the private sector.
Ulster Bank has suffered hefty losses as it counts the cost of loans turned sour since the financial crisis.
The bank - once Ireland’s third-largest lender - was split in 2009 into a core bank and non-core bank, which includes assets the lender plans to sell over time.
It slumped into the red with operating losses of £1.04 billion for the core business in 2012, but it said trading was improving as losses almost halved year-on-year in the first quarter of 2013 to £164 million.
The group has also had to stump up millions of pounds of compensation for customers affected by RBS Group's month-long IT meltdown last summer.
Customers of RBS and NatWest had their banking services back within days, but the chaos lasted for a month in the Republic of Ireland and Northern Ireland.
Jim Brown, chief executive of Ulster Bank, said the overhaul would help it create a "smaller, lower cost and profitable" bank.
It is expected to see the core business break even by the end of next year before returning to profit by 2016 and on a "moderate growth path".
The plans will shave up to £40 million off its cost base, while other actions will deliver up to a further £25 million in savings.
It will also invest in its internet banking service, having already increased the number of online customers by 11% to around 400,000 over the past two years.