The insurance company Aviva is cut almost 1,000 job in the Republic, the company announced on Wednesday.
Aviva, which employs more than 2,000 people in Ireland, had invited staff to meetings in Dublin, Cork and Galway.
The redundancies could take up to two years to implement, but it is thought no jobs will be lost before March next year.
Aviva Ireland will shed 770 jobs with the company’s European division losing 180 posts.
There is also speculation that a further 300 staff will be deployed elsewhere.
Several of the company’s executives, including Aviva Europe chief, Igal Mayer, travelled to Dublin for the announcement.
The union Unite has described the situation as “very worrying”. Regional officer Brian Gallagher said workers did not yet know whether redundancies would be compulsory or voluntary.
After meeting Aviva management on Tuesday, Mr Gallagher said the company had promised to give the union as much time as it needed to work through the proposals.
Aviva said it hoped to create 100 jobs in the health insurance division over time.
The company’s operations in Northern Ireland are part of Aviva UK and are not affected by the announcement in the Republic.
In a statement, Aviva said: “Following a detailed structural review, Aviva is proposing to make its Irish business part of a new UK and Ireland region, aligning many of the activities and services provided for customers.
“There are currently 1,770 employees in the Aviva Ireland business.
“The company anticipates that if the proposals were implemented the number of roles remaining in Ireland would be between 1,000-1,200, including roles which may potentially be outsourced.