Meat workers at eight North Island plants will vote on Wednesday on whether or not to lift a strike notice.
Two days of mediation talks between the Meat Workers Union and meat processing company Affco over a new collective agreement ended on Tuesday with an agreement to hold two more days of talks from May 7.
The long-running dispute has led to about 1000 workers being locked out of Affco's eight North Island plants since the end of February.
The union says the company will lift a lockout notice on 300 workers at 5am on Wednesday. Two-thirds of these workers are from the Feilding and Whanganui plants.
Meat Worker's Union general secretary Dave Eastlake says the 300 workers will only return to work if the union lifts a strike notice.
There will be a vote on that at meetings at 3pm on Wednesday at all eight plants.
"We'll make a decision then whether we will lift the strike notice.
"We've been asked to lift the strike notice but the company won't give any guarantee that they'll lift the lockout notice for 450 other workers," Mr Eastlake said.
The company had indicated it may lift lockout notices for more workers next week but the union was seeking a guarantee they would be lifted for all workers.
The union says that during talks the company has removed a security of employment clause from the collective and has included a new clause that appears to give them the ability to fire union members they don't like, which is unlawful.
NZN