MELBOURNE - Australian battery minerals producer IGO expects Ivan Vella, who was dismissed by his previous employer Rio Tinto this week, to start as CEO in early December as planned, its Chairman Mike Nossal said on Thursday.

IGO had picked the Rio Tinto aluminium chief for its top job in June, when both companies had agreed that Vella would work out his notice at Rio Tinto to ensure a smooth handover before starting at IGO in December.

But Rio Tinto dismissed Vella with immediate effect on Wednesday for a breach of confidential information, an email to all employees sent by CEO Jakob Stausholm and seen by Reuters showed.

Reuters does not know what the confidential information relates to.

"I need to acknowledge the news overnight which relates to Ivan's departure from his previous employer," Nossal told a shareholder meeting.

"The Board is engaging with Ivan to more deeply understand the circumstances ... however, it is our expectation that Ivan will start with IGO in early December as planned," he said.

Vella, who had spent two decades at the mining giant, did not immediately respond to a request for comment via LinkedIn.

IGO conducted multiple formal and informal references, background checks and due diligence on Vella, Nossal said.

"All of the information which came out of this process reinforced the quality of Ivan as a candidate, indicated a high level of integrity and was entirely consistent with his extensive and successful executive career," Nossal said.

IGO has faced difficulties since the sudden passing of its previous CEO Peter Bradford in October 2022.

It flagged a material writedown of nearly A$1-billion in the June financial year due to ballooning capital costs at its newly acquired Cosmos nickel operations in Western Australia.

Also, production of lithium hydroxide at its Kwinana refinery joint venture with China's Tianqi Lithium Corp 002466.SZ has been beset by technical difficulties that have delayed production.