Negotiators for three major supermarket chains and Southern California store clerks agreed to get back to haggling today to try to resolve differences over wages and health benefits.

Talks between the Albertsons, Ralphs and Vons chains and the United Food and Commercial Workers union hadn't been held since Thursday, when the markets refused to meet a union demand for a comprehensive contract offer by noon on that day.

Rhetoric and tensions then escalated over the weekend as the union got strike authorization from its Ralphs and Vons members during a vote Sunday. Albertsons workers had voted in March to authorize a strike.

But Tuesday, spokesmen for the supermarkets and the union said that negotiations would resume today at an undisclosed location, with additional sessions planned for Thursday and Friday. Talks could continue into the weekend if progress is being made, union spokesman Mike Shimpock said.

Both sides have said they are hoping to avoid a repeat of the 141-day strike and lockout of 2003-04 that left many union members deep in debt and cost the employers an estimated $1.5 billion before a contract agreement was finally reached. The contract for 65,000 workers at markets from Bakersfield to the Mexican border has been extended twice since its March 5 expiration.

Ralphs is a division of Kroger Co., which is based in Cincinnati. Vons and Pavilions stores are owned by Safeway Inc. of Pleasanton, Calif. Albertsons is owned by Supervalu Inc. of Eden Prairie, Minn.

Grocery worker contracts have been coming up for renewal around the country, and agreements have been reached recently in some areas.

The Southern California talks have been hung up over several issues, including how to fund the healthcare benefits package. Other important matters, such as a raise for employees, are still in the initial discussion stages, said people close to the talks.

Kroger reached a contract settlement with workers in Texas over the weekend and had already signed an agreement with workers in Michigan, Chief Executive David B. Dillon said Tuesday during an earnings conference call with analysts and investors.

An April strike at a Kentucky warehouse and competition from Wal-Mart Stores Inc. squeezed first-quarter income, which rose a less-than-expected 10% to $336.6 million, or 47 cents a share.

Both of Kroger's recent labor agreements were preceded by strike authorizations, said Rick Icaza, president of United Food and Commercial Workers union Local 770 in Los Angeles. "It's no coincidence that in each instance the union got a strike authorization vote first in both Detroit and Texas," Icaza said.