The union representing hundreds of workers at the Co-op refinery say they are meeting with the company Friday morning.
Workers could be locked out as early as Sunday at the refinery located just outside of Regina.
The cooling off period between the Co-op refinery and Unifor 594 expires at midnight Friday night which means a 48-hour strike or lockout notice can be issued.
Earlier this month, the refinery handed workers what it called its final offer, saying in addition to degrading the pension plan for new employees, Co-op had also demanded two-tiered wages in some areas of the refinery.
Co-op had also stated it wanted to contract out work outside of the union.
Unifor 594 represents 800 employees working at the refinery.
The collective agreement between Local 594 and Co-op expired over one year ago in January 2016.