A 20-year friendship that helped turn Dan Gertler into a billionaire has left the Israeli businessman with a lot fewer places to go. The U.S. government accused Gertler of corrupt mining and oil deals in the Democratic Republic of Congo and said he acted as a middleman to enrich his longtime buddy, President Joseph Kabila.

Sanctions have shut Gertler out of the American financial system, halting access to the dollars that are the main currency used in Congo and in global raw-material deals.

Gertler is being targeted because of the West's deteriorating relations with Kabila, Yuma said.

And then there is Glencore PLC, the global commodity trader that was once Gertler's most important partner in Congo.

Gertler denies paying bribes in Congo to secure mining deals and insists his success reflects a long-standing friendship with the country's 46-year-old president and a track record for delivering results.

Gertler credits himself for bringing more than $7 billion of foreign direct investment to Congo, creating thousands of jobs and helping to make the country Africa's biggest copper producer.

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