The Dairy Workers Union and the Open Country Dairy company are expected to enter another round of mediation this week after reaching a stalemate over allowing union members back into its factory at Waharoa.
A six-week lockout of the 38 employees was ruled illegal by the Employment Court last week, and the company says it's no longer in place.
However, Open Country is not letting them back while investigations continue into what it calls environmental sabotage at the factory.
The union says the company is acting illegally by not allowing its members back to work.
National Secretary James Ritchie says legal advice is being obtained on the matter.