* Alstom posts steepest loss on CAC 40
* Company says is cooperating with U.S. justice dpt
* Too early to speculate on potential settlement -spox
(Adds context, detail from Bloomberg report)
PARIS, March 27 (Reuters) - Shares in Alstom fell on Thursday on the prospect that the French engineering firm could face hefty penalties from the U.S. Justice Department in a bribery probe focused on Asia.
Alstom is cooperating with the U.S. Department of Justice on the probe and it is premature to speculate on its findings or how big a settlement could be, a company spokeswoman said.
Bloomberg earlier reported that Alstom had hindered the U.S. investigation of possible bribery in Indonesia and now faced an expanded probe into power projects in China and India. The report cited court documents and two people with knowledge of the investigation.
The case could result in one of the largest U.S. anti-corruption fines, Bloomberg wrote, drawing comparisons with the $800 million U.S. settlement paid by Germany's Siemens following a global bribery scandal in 2008.
Shares of Alstom fell 6.3 percent at 1157 GMT, making it the biggest loser on the CAC 40 blue-chip index.
An Alstom spokesman said settlement talks had not yet begun with the U.S. investigators and that any attempt to put a number on a potential settlement was "pure speculation".
"The Department of Justice has not said anything to suggest that there are any shortcomings in the scope or direction of the company's current effort," the spokeswoman said in an emailed statement.
"We look forward to amicably resolving with the DOJ any problems that we uncover. But it is far too early to say what projects might be encompassed in a potential settlement or how large such a settlement might be."
The U.S. probe of Alstom has focused on a $118 million contract to provide power services at a power plant on the Indonesian island of Sumatra.
The contract, known as the Tarahan project, was part of a joint venture between Japan's Marubeni Corp and Alstom. It was awarded to both companies in 2004 and finished in 2007.
Two Alstom executives of the U.S. arm of Alstom in Connecticut have so far pleaded guilty to conspiracy to violate bribery laws in connection with the project.
While investigating that deal, the Justice Department found evidence of possible bribery in 10 other energy projects in Indonesia, India and China, Bloomberg reported, citing documents filed in a related case.
(Reporting by Natalie Huet; Editing by Leila Abboud and Stephen Powell)