The walkout has closed at least one fourth of the approximately 400 stores that Walmart Inc operates in Chile. Striking workers carrying protest signs have blocked access to many stores around Santiago.

The company said in a statement that it hoped to continue with constructive dialogue but said it also worried about "the illegal blockades of outlets that have occurred throughout the strike."

Lider's Inter-Company Union (SIL) could not immediately be reached for comment.

Union leaders said the key sticking point was a salary increase. As automation in stores has increasingly replaced workers, workers say they are forced to juggle more tasks among fewer employees. They have demanded the company boost salaries by 4 percent. Walmart Chile has offered 3 percent, the union has said.

The strike has primarily affected Walmart stores under the franchise SuperBodega aCuenta, and, to a lesser extent, Express, Lider and Ekono.

(Reporting by Dave Sherwood; editing by Jonathan Oatis)