Mackie International, the Northern Ireland textile engineering firm, could face closure as a result of a walk out by half its staff, the company's chief executive has warned.

Yesterday, 150 shopfloor staff, acting on the instructions of their works committee, decided to walk out two hours before their shift was due to end.

No representative of the works committee was available for comment but it is understood that a dispute about the position of a shop steward is one of the central issues involved.

The company has called on all the staff to return to work on Monday morning, but the dispute might escalate instead.

Mr Sul Sahota, chief executive, said the "unofficial action is unnecessary and illegal".

"We need all employees to pull their weight and act like team players if the company is to be successful," he said.