Unions representing workers at Waterford Crystal have said its factories in Waterford city and Dungarvan will close next Monday for five days.
A union spokesperson said up to 1,500 workers would be without pay for the week as part of cost-cutting measures by the company. Both factories are expected to resume operations on October 22.
The company is continuing negotiations with the unions in relation to short-time working and it is understood an agreement has not been reached on this issue.
In relation to next week's shut-down, a company spokesperson said he would not comment before talks with the unions had concluded.