Factbox: OPEC+ talks face challenges over baseline for cuts and U.S. role

LONDON (Reuters) - OPEC and its allies are due to hold talks on Thursday to discuss the biggest coordinated supply production cut in history but they must agree on two major points: the levels from which any cuts should be made and how the United States will respond.U.S. President Donald Trump said last week he had brokered a deal between Russia and Saudi Arabia to cut 10 million to 15 million barrels per day (bpd) of crude, or 10 to 15% of global oil supplies. The coronavirus crisis has slashed..