SANTIAGO, March 21 (Reuters) - Chilean miner Antofagasta Minerals on Thursday inaugurated a more than $2 billion desalination plant for its flagship copper mine in Chile, Los Pelambres, aimed at relieving the effects of severe drought that has hit production.

The mine is the first to operate with desalinated water in an area of the country that has suffered a 15-year drought, sucking water from reservoirs and sparking concern over the fresh water supply.

Chilean President Gabriel Boric praised the project, saying the situation in the Coquimbo region, where Los Pelambres is located, is concerning.

"Especially with the climate change crisis, we must be not only a mining country, but also a country at the cutting edge of responsible, sustainable mining," he said at the inauguration for the plant, which is at coast in Los Vilos, a city within Coquimbo.

Antofagasta began construction in 2019 for the plant, and plans to pump 400 liters of water per second for use at Los Pelambres, located about 55 km inland.

The company plans to supply another 400 liters of water per second in a second phase slated for completion in 2027, which it says would relieve pressure on the nearby Choapa river.

Chile's historic drought has impacted nearly ever aspect of life in the nation that is the world's top copper producer. Mining companies outside Coquimbo are already using seawater, particularly in Antofagasta, a northern desert region home to most of Chile's mining activity. (Reporting by Natalia Ramos and Alexander Villegas; Editing by Daina Beth Solomon and David Evans)