Mumbai, June 17 -- In its Monthly Oil Market Report released in June, OPEC highlighted a mixed performance across global commodity price indices for May. The report noted that while base and precious metals indices posted gains, the energy and other mineral indices declined under pressure from ongoing trade uncertainties. Commodity prices overall struggled as fears over global trade tensions weighed on sentiment, despite a 90-day trade truce between the US and China that temporarily eased price swings but failed to fully lift market confidence. The energy price index fell for the fourth straight month in May, down 4.4 percent month-on-month, driven mainly by lower average crude oil and US natural gas prices. Some of these losses were offset...