Management at The Irish Times have told staff it needs to shed 250 of the 710 jobs at the company.
Financial difficulties caused by a severe drop in advertising revenue, combined with steeply rising costs, are being blamed for the cuts.
The figures do not include staff at the newspaper’s Internet arm, ireland.com, which is facing a separate review.
The editor of The Irish Times, Conor Brady, said he realised the news had come as a shock to staff.
He said: “It’s a dreadful day for The Irish Times. We have a problem with costs and we have progressively to bring costs down.”
He said revenues had reached an all-time high at the beginning of the year, before beginning to slide.
Mr Brady has not rejected reports that cuts in the editorial department could be as high as 40 per cent, and he still expected staff would be able to produce a “high-quality newspaper”.
He also gave a commitment to the staff that reductions would “be proportionate across all departments and take place as equitably and fairly as possible”.
He was confident The Irish Times would maintain what he called its unchallenged place as the leading newspaper in the country in terms of its authority, depth and range of editorial content.
“The newspaper’s character and ethos remain the same,” he said.
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