Oil prices were mixed on Tuesday as energy market participants closely monitored the potential for fresh talks between the U.S. and Iran in Qatar. International benchmark Brent crude futures with August delivery were last seen down 0.1% at $73.13 per barrel, paring earlier losses. The contract is on track to end June roughly $20 lower, or 21% lower than the closing session on May 29. Brent crude futures with September delivery , meanwhile, rose 0.2% at $74.08. U.S. West Texas Intermediate futures with August delivery traded 0.2% higher at $70.89, putting the contract on course for a $17 drop, or 19% fall, from last ... (full story)