SANTIAGO - Chile's leftist President on Thursday said he would oppose a proposal from conservative leaders in Congress to allow private lithium concessions, arguing that his state-centred approach was the better bet.

Earlier this year, President Gabriel Boric pitched a sweeping reform that would ensure that future developments of the coveted battery metal remain firmly under government control.

"As long as I'm president, lithium will belong to all Chileans," Boric said at an event in the capital Santiago. "That's why we're against this initiative."

Chile is a leading global producer of the metal seen as key to the transition away from fossil fuels.

Under Boric's April plan, future lithium contracts would only be issued as public-private partnerships under the government's control.

Since then, Boric has suffered major legislative defeats in Congress, though his lithium reform largely does not require legislative approval.

Opposition conservative lawmakers who oppose Boric's approach made the legislative proposal in a bid to eliminate a long-standing prohibition on granting concessions for lithium development.

Currently, mining industry giants SQM and Albemarle lead Chile's production of the ultra-light metal used to make lithium-ion batteries for a wide variety of consumer electronics as well as future fleets of electric vehicles.

The projects operated by the two firms stem from lease deals overseen by state agency Corfo.

Chile originally reserved lithium developments to the government at a time when the metal was seen as primarily required for nuclear power plants.

The South American country was the world's second biggest producer of lithium last year, according to estimates from the US Geological Survey.

It forms part of the so-called lithium triangle with Argentina and Bolivia, which are together believed to hold more than half the world's lithium resources.