US supermarket chain Ralphs has announced plans to permanently close 15 underperforming Ralphs supermarkets in Southern California within the next 60 days.

Ralphs, a unit of US retailer Kroger Co, said the store closures are not related to the recently resolved Southern California supermarket labour dispute. 

Ralphs said it made the decision to permanently close the 15 stores following its annual review of its supermarket operations. The company said each of the stores slated for closure has experienced declining sales over an extended period of time. 

“We are taking these steps after extensive and careful review,” said John Burgon, president of Ralphs. “The closing of these stores is a difficult but necessary step toward a better, more competitive Ralphs in Southern California. None of these stores generates enough sales, nor has enough customers, to pay for the increasing cost of their operation. Closing these stores will help us operate more efficiently and position Ralphs for the next generation of growth by better serving our customers.” 

The company said the closures would affect 600 employees and it intends to transfer them to other stores where possible.