A recovery in U.S. oil output may deter OPEC and non-OPEC producers from extending production cuts beyond June and might lead to a new price war, Russia’s top oil major said on Monday. U.S. shale oil production had been in retreat as oil prices tumbled from above $100 a barrel in 2014 to below $30 in 2015, making costly fracking processes less profitable. A deal by the Organization of the Petroleum Exporting Countries with Russia and other producers to rein in output by 1.8 million barrels per day (bpd) for six months from Jan. 1 lifted prices but also encouraged U.S. firms to boost supplies. “It became evident that U.S. shale oil output has become and will remain a new global oil price regulator […]