BP will team up with the government of Iraq to rehabilitate and develop four oil and gas fields in the northern region of Kirkuk. The two sides signed a preliminary agreement to that effect this week. The deal follows another one, signed in 2013, for the development of the giant Kirkuk field, which is estimated to hold some nine billion barrels of recoverable crude. That deal was put on hold a year later, however, amid the Islamic State’s advance across the Middle East. Following the war with IS, the autonomous region of Kurdistan claimed…