BHP Billiton could face enforcement action by US officials over alleged breaches of anti-corruption laws, it admitted.
The move relates partly to corporate hospitality that the London-listed miner laid on for the Beijing Olympics in 2008.
The Securities and Exchange Commission and US Department of Justice have been investigating BHP since 2009 over exploration projects that have been terminated and hospitality given at the Beijing Games, where the miner was a major sponsor.
"As a part of the US process, the SEC and DoJ have recently notified [us] of the issues they consider could form the basis of enforcement actions, and discussions are continuing," BHP said yesterday.
"The issues relate primarily to matters in connection with previously terminated exploration and development efforts, as well as hospitality provided [at the 2008 Games]."
It said it could not comment on the possible outcome or the scale of any penalty. It could face multimillion-dollar fines.
The French oil giant Total recently agreed to pay $398m (£256m) to settle US criminal and civil allegations that it paid $60m in bribes to win oil and gas contracts in Iran
Levels of penalty for breaching the US Foreign Corrupt Practices Act vary depending on the length of time and depth of the violations, the financial benefits to the company concerned, and its co-operation with any investigation.
Last year the medical products supplier Smith & Nephew paid $22.2m to settle a claim that one of its subsidiaries bribed a Greek distributor. In 2010 BAE Systems paid almost $500m to the DoJ and the Serious Fraud Office to settle allegations of longstanding bribes paid to Saudi officials, among others.
Australian authorities are also investigating BHP's dealings with foreign officials, including Chinese dignitaries at the Games. Other issues said to be under scrutiny include payments to Cambodian officials in 2006 over a bauxite project that BHP eventually dropped.
The miner said: "BHP Billiton is fully committed to operating with integrity, and the group's policies specifically prohibit engaging in unethical conduct.
"The group is fully co-operating with the relevant authorities."
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