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SANTIAGO, July 20 (Reuters) - Union-represented workers and management at Antofagasta's Zaldivar copper mine failed to reach a wage deal on Thursday and they agreed to extend government-mediated talks into next week, the union said.
Last week, the union voted to strike, prompting the mediated talks and a new contract offer.
But workers rejected that offer Thursday, union president Raul Torres told Reuters.
"The members of the Zaldivar union after not accepting the proposal made by the company in mediation have agreed with (the company) to extend mediation until next Wednesday with the aim of discussing and receiving a new proposal," he said.
Antofagasta did not immediately respond to requests for comment.
Zaldivar produced just over 100,000 tonnes of copper last year, out of the 5.5 million tonne total produced by Chile, the world's top producer.
Reporting by Fabian Cambero; Writing by Rosalba O'Brien; Editing by Sandra Maler and Leslie Adler