Unite has written to the Minister for Finance, Michael Noonan, warning him of possible industrial action at AIB.
The trade union, which represents over 200 members at AIB, said there is a rapidly deteriorating industrial relations climate at the bank.
It said the disagreement centres on pension arrangements for former EBS staff, who are now employed by AIB. Unite says the bank faileto honour a pension agreement concluded in 2009, which envisaged the employer – then EBS – increasing its contributions in tandem with increased employee contributions
Unite regional officer Colm Quinlan said the company has "consistently refused to engage" with Unite, not only in respect of trade union members' pension scheme but also in respect of individual workers.
“The most recent example of management’s refusal to engage was their breath-taking decision to notify us by text message of this week’s outsourcing proposals”.
Mr Quinlan said the company’s determination to avoid engagement with Unite “does not bode well for the pay discussions due to commence during the next few months”.