US supermarket giants Safeway, Kroger Co. and Supervalu have a claimed a boost in contract talks with workers in southern California.

The companies have received an indication that employees have approved a new four-year deal, although they are awaiting official confirmation from the unions.

The deal covers more than 65,000 employees, who work at nearly 800 Vons, Ralphs and Albertsons stores throughout southern California.

"This new agreement will provide employees with the best wages, benefits and working conditions in the Southern California retail market," said Safeway chairman, president and CEO Steve Burd.