94 jobs are to go in Cork with the closure of GSK's financial services operation, which is located in the city.
The operation is set to be relocated to Britain as part of a global restructuring by the company.
Staff were briefed by company management at an on-site meeting lunchtime today.
However, a spokeswoman for GSK said staff had been told last May that a restructuring process would see the closure and relocation of the Cork operation to Britain.
The operation is to be wound down before the end of the year, while the spokeswoman said staff would be offered the option of re-locating to the UK.
The company currently employs 1,600 people in Ireland at three manufacturing sites in Cork, Sligo and Dungarvan, and at two commercial operations based in Dublin.