NOC, Libya's state oil firm, has identified its second-ranking official as the company's acting chairman, apparently confirming media reports that veteran chairman Shokri Ghanem has left the post.

Ghanem's departure is likely to be viewed as a setback by foreign oil majors, including BP and ExxonMobil which have invested millions of dollars in Libya and regarded the reform-minded Ghanem as a reliable partner.

The company made no direct announcement about Ghanem leaving his job, but in a statement on its Internet site about a September 9 meeting with a delegation from German utility RWE, it referred to Azzam al Messallati as NOC's acting chairman.

Previously, al Messallatti's official title had been member of the NOC administrative board, but he was also Ghanem's de facto number two in the company.

In the statement posted on its Internet site about the September 9 meeting, NOC said only that 'Libya's National Oil Corporation acting chairman Azzam al Messallati met German energy group RWE's deputy chairman'.

An independent news portal, Libya Today, reported last month that Ghanem had handed his resignation to Libyan leader Muammar Gaddafi, but there has been no direct confirmation of this.

Investment risk

Libya is home to Africa's largest proven oil reserves and in the past decade foreign investors have rushed to capitalise on the lifting of international sanctions and the country's emergence from isolation.

BP CEO Tony Hayward signed a deal with Libya in 2007 worth at least $900 million, in what the company described as its single biggest exploration commitment worldwide.

However, foreign investors' initial enthusiasm has been tempered by modest results from exploration wells and concerns about the risks of dealing with Libya's government.

Some investors say the treatment of Canadian energy producer Verenex, whose shares fell sharply after Libya denied approval for a takeover by an arm of China National Petroleum Corp., underlined Libya's unpredictability.

Ghanem, who is 66, was Libya's Prime Minister from 2003 until 2006 and before that held senior positions with the Organization of the Petroleum Exporting Countries at its headquarters in Vienna.

'Were Ghanem to resign, foreign firms would lose their most competent interlocutor on the Libyan side,' Geoff Porter, Middle East and Africa director for the Eurasia Group consultancy, wrote in a research note earlier this month.

'Ghanem has always been seen as something of a reformer and his replacement would likely be more politicized.” – Reuters