FinanceOil plunges on easing supply concernsBrent and WTI fall at one point on Tuesday to lowest levels since 25 February as Russia says it favours resumption of Iran nuclear dealShaking on it: Russian Foreign Minister Sergei Lavrov shakes hands with Iranian Foreign Minister Hossein Amir-Abdollahian during a joint news conference in MoscowPhoto: REUTERS/SCANPIXReuters