The Associated Press reports that Exxon Mobil Corp., the world''s second-largest integrated oil company, on Monday said it agreed to acquire a 28 percent stake in an oil field in the Arabian Gulf from Abu Dhabi National Oil Co., for an undisclosed sum. Abu Dhabi National will be left with a 60 percent interest in the Upper Zakum oil field off the coast of the United Arab Emirates. Japan Oil Development Co. will continue to hold the remaining 12 percent interest. Exxon Mobil said the three companies, through their Zakum Development Co. joint operating company, plan to increase production by about 50 percent to a target of 750,000 barrels of oil per day. Under the acquisition agreement, Exxon Mobil said it will support drilling activities, establish a technology center in Abu Dhabi and provide support for personnel training.