Update 4.30pm: One of the world's largest machinery companies is considering shedding up to 250 people in the North.
Caterpillar, the world's largest manufacturer of heavy construction equipment, said it had been been hit by a global downturn in mining and oil exploration which has reduced demand for its products.
It employs 1,800 people across the North.
Up to 250 jobs could go at the US multinational's plants in the North, a spokesman confirmed.
The proposals include the possible closure of the Monkstown facility near Belfast and the consolidation of operations in Larne in Co Antrim and Springvale in Belfast.
The manufacturing firm is considering discontinuing production of 25-ton and larger material handlers in Northern Ireland, including the planned launch of large material handler models for Europe.
If finalised, production for electric power generator sets in Monkstown would be consolidated into Larne and manufacture of truck axles will move into Springvale.
A company statement said: "These actions could result in the reduction of between 200 to 250 production, support and management positions across the Northern Ireland facilities."
It has four facilities - Larne, Monkstown, Springvale and Belfast offices beside the Springvale plant.
It makes generator sets and carries out other forms of manufacturing, including the assembly of axles for articulated trucks and the manufacture of wheeled material handlers.
It also has a shared services centre in Belfast with people employed in areas including finance and human resources.
The generator sets are used for prime and standby electric power for customers such as hospitals, utilities and data centres.
One of the largest machinery companies in the world is expected to announce large scale job losses in Belfast today.
Staff at Caterpillar's West Belfast plant have been called to a briefing this afternoon - it is after workers at the heavy machinery factory were told not to turn up for their night shifts last night.
The company has shed over 1,000 jobs in Northern Ireland in the past five years as part of a global restructuring plan.
The SDLP's Alex Attwood says no stone should be left unturned in making sure jobs are protected: "Everybody is anticipating bad news, the issue is what is the scale of that bad news and will it see the close of one or more than one plant completely.
"Those are the issues and the concerns for the families not least on the week that their children have gone back to school."