Chinese electric car-maker BYD has held talks with Brazil’s Sigma Lithium over a possible supply agreement, joint venture or acquisition, the Financial Times reported on Sunday.

BYD met Sigma Chief Executive Ana Cabral Gardner in Sao Paulo last month, BYD’s Brazilian chair, Alexandre Baldy, told the newspaper, but did not give details, citing a confidentiality agreement.

BYD and Sigma did not immediately respond to Reuters requests for comment.

Sigma said in January it had initiated a primary listing of Sigma Brazil on Nasdaq and the Singapore stock exchange.

BYD, backed by Warren Buffet’s Berkshire Hathaway, said in July it would invest 3 billion reais ($600 million) in a new industrial complex in northeastern Brazil, with operations expected to start in mid-2024.

($1 = 4.8539 reais)