Prince served as an unofficial representative for the U.S. president at a secret meeting in January in the Seychelles islands that was designed to set up a backwater channel with Russia, Arab, European and U.S. officials told the newspaper.
The meeting, which took place in January, was convened by the United Arab Emirates, NBC News confirmed.
Prince reportedly met with a Russian envoy with ties to Vladimir Putin. The Russian was not identified.
It is not fully clear what the agenda for the meeting was, although the Post reports that the UAE was hoping the Americans would be able persuade Russia to distance itself from Iran, a move that would likely force the U.S. to ease sanctions on Russia.
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The meeting reportedly took place in early January, more than a week before the Trump inauguration.
While Prince has no official ties to Trump, he visited the Trump transition office in New York in December and is said to have donated more than US$250,000 to Trump’s campaign last year.
Prince’s sister, Betsy DeVos, is education secretary in the Trump administration.
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Blackwater was a U.S. security company that made front-page news in 2007 after a serious of abusive incidents including one in which several of the company’s employees were convicted of killing Iraqi civilians in 2007.
The FBI has been looking into the Seychelles meeting as part of an investigation into Russian interference in the U.S. election, the Post reported.
Sources told the Post that the UAE prince who brokered the meeting, Sheikh Mohammed bin Zayed al-Nahyan, would never have set it up without the approval of Trump and Putin.
The meeting was said to be productive but the idea of any further meetings was deemed to be too politically risky, the Post reported.