The United States is planning to impose a major new regulation on offshore oil and gas drilling to try to prevent the kind of explosions that caused the catastrophic BP Plc (BP.L) oil spill in the Gulf of Mexico, the New York Times reported on Friday, citing Obama administration officials. The Interior Department could make the announcement as early as Monday, the paper said. The rule is expected to tighten safety requirements on blowout preventers, devices that are the last line of protection to stop explosions in undersea oil and gas wells, the Times reported.