Around 140 jobs are to be lost at US manufacturing giant Caterpillar's plants in Northern Ireland, a union said.
Sixty-five permanent employees will be laid off through a voluntary redundancy scheme, the company confirmed, and it is understood around 75 temporary agency workers could also go.
The action is due to weaknesses in the economies of key markets and falling demand for products.
Unite union said the cuts would affect three production sites in Larne, Monkstown and Springvale in west Belfast.
Davy Thompson, regional coordinating officer at the union, said: "The timing of this announcement is particularly difficult for the workforce coming in the mouth of Christmas."
Founded in 1966, Caterpillar (NI) Limited is Europe's largest diesel power generating set manufacturer.
Products are exported throughout the globe and directly support key business sectors including the telecoms, healthcare, tourism/leisure, retail and banking industries.
The workforce in Northern Ireland totals around 2,000. The job losses among employees will include 20 from Larne, 30 from Monkstown and 15 from Springvale, the company said.
A spokesman said: "Current weaknesses in the economies of some key markets are impacting on demand for some of our products.
"The company is therefore taking appropriate measures during this time to help ensure the competitiveness of the business.
"We will continue to closely monitor the economic environment and will continue to communicate with employees."
This is the latest in a series of job losses across Northern Ireland's manufacturing sector. Over the last couple of months cuts have been announced at Bombardier Aerospace and the JTI/Gallaher's tobacco factory in Ballymena.
Mr Thompson added: "This announcement highlights the inadequacy of existing employment protection, in particular for manufacturing and agency workers.
"There's a need for Stormont politicians to take action to improve job security protections for workers."
He said that since 2008 output from Northern Ireland's manufacturing sector has shrunk by 9%, meaning many highly skilled workers who will lose their jobs at Caterpillar will struggle to find employment.
"This decision reinforces the need for the Northern Ireland Executive to initiate a substantial and wider industrial investment and manufacturing strategy to address the range of serious economic challenges we face."