Staff at Bank of Ireland are to stage a 24-hour stoppage on 8 July in a dispute over bonuses.
Of the Bank of Ireland employees who belong to the Irish Bank Officials Association, 92% have voted to support limited industrial action.
Their stoppage will coincide with the bank's Annual General Meeting.
The move follows BoI's decision to halve annual bonuses for staff, agreed in a recent restructuring deal, from 6% to 3%.
The IBOA has estimated the cost to individual staff members at between €2,400 and €5,900 each.
Under a strategic transformation programme negotiated in 2005, staff were to receive up to 6% of salary in free shares under a gain-sharing arrangement.
However, the agreement was conditional on Bank of Ireland meeting financial targets relating to earnings per share growth and cost management.
The bank announced recently that while its cost saving targets had been met, earnings per share targets had not.
As a consequence, it considered that a 3% share bonus would be fair and equitable in the interests of all stakeholders - including employees and investors.
The bonus scheme will cost the bank €20m.
The IBOA has described the move as a serious breach of trust which would demotivate staff.
General Secretary Larry Broderick said staff had met their side of the bargain, delivering 2,100 job cuts and savings worth €147m a year.
They criticised the bank for making a public announcement before referring the matter to arbitrator Kieran Mulvey.
After meeting both sides some weeks ago, Mr Mulvey said he was unable to make a recommendation because the two sides are so 'polarised'.
