MELBOURNE- Rio Tinto CEO Jakob Stausholm said on Tuesday the global miner is focused on small, bolt-on acquisitions to shape its portfolio and is looking at a number of potential lithium acquisitions but added the sector remains quite hot.

The boss of the world's biggest iron ore producer has said that he wants Rio Tinto to focus on being the world's best operator rather than conducting huge buyouts that would change the nature of the company and divert the focus of the group.

"I don’t think we need a big acquisition right now," Stausholm said at an event in Melbourne.

"What we are trying to do is a bit of smaller portfolio acquisitions ... that shapes the portfolio."

The Australian miner has already announced several small partnerships and deals this year, including the purchase of a 57.74% stake in the Agua de la Falda copper project in Chile on Monday.

Earlier in July, Rio Tinto agreed to buy a 15% stake in Australia's Sovereign Metals  for A$40.4-million ($27.04-million) to help develop a rutile and graphite project in Malawi.

Rio was looking at a number of possible lithium interests, Stausholm said, but the market for energy transition metals like copper and lithium was "pretty hot".

"I wouldn't mind having lithium production in Canada," he said.

Rio wants to raise its lithium exposure, and Quebec, home to Rio's green aluminium operations, is a hot spot for new hard rock lithium deposits, with battery chemicals makers setting up shop in the region ready to supply the U.S. electric vehicle market.

In the latest deal in the race to secure lithium assets and on Rio's doorstep, top global producer Albemarle agreed to invest C$109-million ($82.5-million) for about a 5% stake in Canada-based Patriot Battery Metals, which this week said its Quebec resource was the largest hard rock lithium deposit in the Americas.

Rio has been off to a sputtering start in the sector, with its Jadar lithium deposit in Serbia on ice after local opposition and with costs doubling at its Rincon project in Argentina.