SANTIAGO: Workers at the world’s largest copper mine in northern Chile went on strike on Tuesday after failing to reach a labor agreement with Australian group BHP, their union said. Unions have long demanded that one percent of shareholder dividends for the Escondida mine, which produces 5.4 percent of the world’s copper, be distributed among workers. On Tuesday, their union said in a statement that “a legal strike started today” over unmet demands that also include shorter work days, bigger bonuses and compensation for total years worked. Media reports in Chile said the company had offered the 2,400 union workers a one-off bonus of nearly $29,000, lower than the $36,000 demanded. Chile is the world’s largest copper producer with annual production of more than five million metric tons, nearly a quarter of global output. When workers at the mine went on a 44-day strike in 2017 — the longest in Chile’s mining history — BHP lost $740 million, contributing to a 1.3 percent decline in the country’s GDP. Escondida, which is an open-air mine located in Antofagasta, produces close to 1.1 million tons of copper a year. In a statement, BHP regretted the workers’ decision, saying it had made “consistent efforts throughout the process to present proposals which contained substantial improvements to the current contract, which is already one of the best... in the industry.” The company said it had activated a contingency plan to deal with the strike, but did not provide details.