(Reuters) – The negotiations between Kellogg NYSE:) Co. and the union representing U.S. cereal plant workers failed again. Two union leaders claimed Tuesday that this was a continuation of a strike that began in October.

Workers went on strike after contracts expired on the previous day. Negotiations about payment and benefits were stalled by differences between Kellogg and approximately 1,400 union members from Kellogg’s cereal plants.

Union members claimed that Kellogg suggested a dual-tier system of employment, but did not offer temporary workers, which make up 30% of Kellogg’s workforce, the opportunity to progress into permanent employees with higher benefits and better pay.

On Tuesday, the union provided an update stating that it had not resolved issues related to the two-tier system. It also offered to meet with Kellogg again in the week beginning Dec. 6.

A request for comment was not answered by the company immediately.

Kellogg has been forced to hire temporary workers in the wake of the strike. They will also have to buy cereals from China to maintain supply. This is a major setback for corporate America, already struggling to cope with rising costs.

An earlier in the month, the union rejected a revised proposal.