ExxonMobil and other leading oil companies are to face an investigation into how up to $500m (£310m) came to be paid into a private US bank account, said to be solely controlled by the President of Equatorial Guinea.
The scandal follows revelations last week that the US Justice Department is investigating whether Mobil Oil Corp, now part of Exxon-Mobil, participated in a plan to route $78m to the Swiss bank account of Kazakhstan's President, Nursultan Nazarbaev, and other senior officials.
Global Witness, a London-based anti-corruption campaign group, has written to John Ashcroft, the US Attorney General, asking him to look into allegations that Equatorial Guinea's ruler, Teodoro Obiang Nguema Mbasogo, has between $300m and $500m deposited in the Dupont Circle branch of Riggs Bank in Washington, DC.
"This situation points to a fundamental problem in the oil business – there is no transparency about company payments to national governments," says Gavin Hayman, who monitors Equatorial Guinea for Global Witness. "President Obiang appears to have taken advantage of a rash of secret deals with US companies to privatise his country's oil wealth to support his brutal regime and his extravagant personal spending."
ExxonMobil and Riggs declined to comment. President Obiang has declared the destination of the country's oil wealth a "state secret".
In June, Tony Blair is to host a transparency conference in London aimed at tackling the corruption that surrounds the exploitation of natural resources in developing countries. Equatorial Guinea is the only oil-producing country to have refused to attend.
Equatorial Guinea has become a major oil and gas producer in the past 10 years, yet the 500,000-strong population remains in poverty. President Obiang has ruled since 1979, when he deposed and executed his predecessor and uncle. His corruption and human-rights record was so bad that the Clinton administration cut its ambassadorial ties. However, he was one of 10 African leaders invited to meet George Bush last year to discuss the "war on terror".
Equatorial Guinea's oil production has jumped from just 17,000 barrels per day in 1996 to a current rate of more than 220,000 barrels.
Details of the Riggs Bank account have emerged after the country's ambassador, Teodoro Biyogo Nsue, who is President Obiang's brother-in-law, unwisely mentioned that oil revenue was held at Riggs during a presentation late last year at the Centre for Strategic and International Studies in Washington.
An investigation by the Los Angeles Times alleged that President Obiang is the account's sole signatory and more than $300m of the country's energy earnings has been deposited in the account by oil companies active in Equatorial Guinea, including ExxonMobil and Amerada Hess.
Alejandro Evuna Owono, a Guinean aide, denied to the LA Times that the government was secretive about oil revenue. "The IMF and the World Bank know national production figures, but we can use the money as we see fit," he said.
Two years ago President Obiang bought a mansion in Potomac, a suburb of Washington, DC, for $2.6m and another home in Rockville, Maryland, for $1.15m.
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