The Chilean Escondida copper mine union said on Sunday it had signed an agreement with BHP Group (BHP.US) that removed the risk of further strikes at the mine, which could have threatened global metal supplies.

BHP said the three-year agreement included changes to working conditions, such as “optimising shift patterns, increasing equipment utilisation and adhering to a 40-hour work week”.

BHP did not provide further details of the agreement, but earlier reports said the company had offered workers about $320,000 in bonuses, while the union had sought 1 per cent of shareholders’ dividends from the mine, or about $350,000-$360,000 in bonuses per worker.

Escondida, which produces more than 1m tonnes of copper a year, accounts for about 5 per cent of global copper production and is the world’s largest single copper supplier. The mine is owned by a number of global mining companies, including BHP, which owns more than half.

Copper prices on the London Metal Exchange rose 1 per cent recently, as metal prices generally rose.