SAN DIEGO — A collection of labor unions representing tens of thousands of Southern California grocery store workers has voted to authorize a strike “should that become necessary.”

The vote, announced Saturday after several days of polling, does not immediately trigger a strike for the roughly 47,000 employees represented by seven United Food and Commercial Workers locals. But it marks the latest escalation in a dispute over a variety of issues from wage increases to COVID-19 hazards and outsourcing.

Union members work at more than 500 stores belonging to Ralphs, Vons, Pavilions and Albertsons. The locations range from central California to the southern border, including San Diego County. If workers did go on strike, it would be the first time since they walked off the job in 2003, a highly disruptive action that lasted about four months.

Union leaders have said they are looking for a $5-per-hour rate increase over the course of a new three-year contract, along with increased safety standards and “adequate scheduling and hours.”

Labor officials have accused the stores of using “small, token bonuses” to make workers feel “intimidated and bribed into accepting a bonus rather than a permanent wage increase.”

“Nobody wins a strike,” Ralphs declared in a news release responding to the vote Sunday. The company said its stores will remain open even in the case of a strike and touted its counter-offer to increase wages by $141 million over the next three years.

A checker with five years experience — who currently earns $22.50 per hour — would see an annual increase of 60 cents per hour until 2024.

“All associates would receive wage increases through the life of the contract and top rate associates would receive a nearly $2 hourly increase to their current industry-leading pay,” the company wrote. “The current proposal would not require any increases in health care costs for associates.”

Workers quoted in union materials and in recent news coverage characterize the offers as insincere and inadequate, particularly after the challenges of working through the coronavirus pandemic.

“The wages on the table are a slap on the face,” Tracy Rebello, a grocery clerk who has been with Ralphs for more than 30 years, told the San Diego Union-Tribune.

“Everything has gone up,” she said. “My wages haven’t.”

Negotiations between UFCW and the companies resume Wednesday. No dates have been set for a strike, should one be called.

In the 2003 work stoppage, some analysts estimated the cost to supermarket chains as high as $2 billion, with the workers losing $300 million in wages, City News Service reports. In 2019, the workers authorized a strike but later reached a contract without walking out.