(Bloomberg) -- Sasol Ltd., South Africa’s biggest company by revenue, said it’s held meetings with shareholders as dissatisfaction grows with cost overruns at the $13 billion Lake Charles chemical project in the U.S.

The meetings began after Sasol raised the estimated cost of the project by $1 billion in May, having increased it only three months earlier, the company said in a response to questions. On Aug. 16 Sasol, delayed its annual results, saying it hasn’t completed a review of the problems at the project. That prompted its shares to fall the most in 20 years on an intraday basis in Johannesburg.

“The chairman of the Sasol board of directors together with management has held meetings with a number of shareholders to hear their views, concerns and expectations,” the company said on Monday. “With regard to the specifics of the shareholder meetings, it would not be appropriate for Sasol to comment on behalf of our shareholders on their expectations.”

Problems at Lake Charles, in Louisiana, have hampered Sasol’s plans to expand internationally and to increase chemicals manufacturing alongside its core fuel-production business. The company’s market value has halved to 169 billion rand ($11 billion) over the past 12 months, making it the third-worst performer on an index of Johannesburg’s 40 biggest stocks.

Representatives of Allan Gray Ltd., which owns 3.4% of Sasol’s stock according to data compiled by Bloomberg, have met with Sasol’s board about the Lake Charles project, said Andrew Lapping, the chief investment officer of the Cape Town-based fund manager. He declined to comment on the talks.

Coronation Asset Management, South Africa’s second-biggest money manager by assets under management which owns Sasol stock, declined to comment.

To contact the reporter on this story: Antony Sguazzin in Johannesburg at asguazzin@bloomberg.net

To contact the editors responsible for this story: John McCorry at jmccorry@bloomberg.net, Rene Vollgraaff, John Bowker

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