Nationwide strike authorized by Costco union representing 18,000 workers.

• If a contract agreement is not reached by January 31, the Costco Teamsters will approve a strike.
• The union represents more than 18,000 employees nationwide.

If the labor group and retailer fail to reach an agreement, a union representing thousands of employees will authorize a strike, leading to a work stoppage.

The Teamsters union, representing 18,000 employees nationwide for Costco, announced that 85% of its members voted in favor of the action. The current contract between the Teamsters and the wholesaler will expire on January 31.

""If Costco's greedy executives fail to act within two weeks, they will be solely responsible for the strike by our members," said Sean M. O'Brien, general president of Teamsters."

The well-known retailer could face negative public sentiment if a strike occurs, as it has been known for its positive treatment of workers and diversity and inclusion initiatives.

The union announced that it will negotiate with Costco for a final week, and it practiced pickets in preparation for a potential strike last week in San Diego and Long Island, New York.

Earlier this year, the union stated that Costco rejected its proposal and deemed its counterproposal "insulting," as it did not reflect the company's "historic financial success" and did not improve retirement benefits.

"The strike vote is a direct response to Costco's greed and disregard for the bargaining process, as stated by Tom Erickson, director of the Teamsters Warehouse Division, in a press release. Despite Costco's claims of treating workers better than the competition, the company is currently failing to uphold its reputation. Management has only two weeks to fix the issue, or they will face the consequences."

Costco did not respond immediately to CNBC's request for comment.