Hewlett-Packard said today its corporate reorganisation would cut a total of 55,000 jobs, at least 5,000 more than its previous estimate.
The US tech giant, which also today announced plans to split in two to achieve a sharper focus, said it had increased its prior estimate of 45,000 to 50,000 job losses "independent of the separation transaction."
HP is to split into two listed companies, separating its computer and printer businesses from its faster-growing corporate hardware and services operations.
In Ireland, HP has over 4,000 employees working in manufacturing, research and development, customer software support, marketing, and sales and services.
The main site for HP in Ireland is located in Leixlip, Co Kildare, and it also has offices in Galway, Belfast and Dublin. It is not yet known how - or if - the extra job cuts will affect HP's Irish operations.
Meanwhile, HP's split move will result in a monumental reshaping of one of technology's most important pioneers, which still has more than 300,000 employees and is on track to book $112 billion in revenue this fiscal year.
The printing and personal computing business, to be known as HP Inc, will be led by Dion Weisler, currently an executive in that division.
HP's current chief executive, Meg Whitman, will lead the new Hewlett-Packard Enterprise, which will house the corporate hardware and services operations. She will also be chairman of HP Inc.
Current HP lead independent director Patricia Russo will be chairman of the enterprise company.
Founded by Bill Hewlett and Dave Packard in a California garage in 1939, HP was one of the companies that shaped Silicon Valley and the PC revolution.
Lately, however, it has struggled to adapt to the shift towards mobile computing, and it has been overshadowed by younger rivals. Its market value of $66 billion is dwarfed by Apple's $596 billion and Microsoft's $380 billion.
Today's announcement confirmed a report of the split in the Wall Street Journal over the weekend.
HP is the latest in a line of companies, often under shareholder pressure, to spin off operations in an attempt to become more agile and to capitalise on faster-growing businesses.
Last week online auction company eBay said it would spin off electronic payment service PayPal.
Up to Friday's close, HP's stock had risen nearly 26% this year.