Chile wants to have three or four new lithium projects operational by 2026, the country's Minister of Finance Mario Marcel said on Saturday.

The South American country - the world's largest copper producer and the second-largest producer of lithium - initiated a policy last year to increase state control of the strategic metal needed in batteries for electric vehicles.

Marcel spoke following a meeting with US Treasury Secretary Janet Yellen, who has been touring the country.

On Saturday, Yellen visited the U.S. lithium producer Albemarle in northern Chile, saying expanded US-Chilean ties would benefit both countries, improve energy security and help achieve key climate goals.

There are currently only two producers of lithium in Chile - Albemarle and SQM - with investors still waiting for the left-wing government of President Gabriel Boric to define its national lithium strategy as it seeks public-private partnerships to develop its lithium salt flats.

Earlier this week, Chile's mining minister said the government had hoped to finalise lithium exploration tenders in the first quarter of this year for private companies.

Chile's state-owned copper mining company, Codelco, has been selected to represent the Chilean state in the new public-private model for lithium as Boric seeks to expand the long-stalled industry.