Global miner Rio Tinto will invest $350-million at its Rincon lithium plant in Argentina as it works to begin production by the end of the year, the company said this week following CE Jakob Stausholm's visit to the site.

"The hard work of our Rincon team is laying the groundwork for our first lithium production by year's end," he said in a statement to Reuters late on Monday, after a recent trip to the project in the northern province of Salta.

Rio Tinto, the world's biggest iron ore producer, is one of the few large mining companies betting on lithium even as counterparts such as BHP stay away from investing in the metal, which is used in electric vehicle batteries.

The company purchased the Rincon project from Rincon Mining in 2022 for $825-million and plans to develop a battery-grade lithium carbonate plant with an annual capacity of 3 000 tons.

Rio Tinto said it is working with local communities and authorities to ensure environmental standards.

Argentina, part of a so-called "lithium triangle" with Chile and Bolivia which holds half the world's resources of the mineral, has increasingly attracted investment from international lithium miners.

The country's lithium production increased more than 45% from 2022 to 2023, according to the US Geological Survey, reaching 9 600 metric tons.