OPEC could raise oil output from July if Venezuelan and Iranian supply drops further and prices keep rallying because extending production cuts with Russia and other allies could overtighten the market, sources familiar with the matter said. Venezuelan crude production has dropped below 1 million barrels per day (bpd) because of U.S. sanctions. Iranian supply could fall further after May if, as many expect, Washington tightens its sanctions against Tehran. The combined supply cuts have helped to drive a 32 percent rally in crude prices this year to nearly $72 a barrel, prompting pressure from U.S. President Donald Trump for OPEC to ease its market-supporting efforts. OPEC has been saying the curbs must remain, but that stance is now softening. […]