A US trade adviser appointed by Barack Obama orchestrated a deal to buy gold worth millions of dollars from a wanted Congolese warlord, according to a UN report. Kase Lawal, a Nigerian-born US oil tycoon, transferred millions of dollars to the notorious rebel leader Bosco Ntaganda between December 2010 and February 2011 as part of the deal, the report by the UN's Group of Experts on the Democratic Republic of the Congo (DRC) states.If true, this would be a contravention of UN resolutions banning individuals or organisations from financing illegal armed groups in the wartorn eastern DRC.