Boeing is close to finalizing a delayed order for 150 737 MAX jets from Turkish Airlines after the carrier threatened to abandon the deal over engine-maintenance terms, four people familiar with the matter said. The order is part of a 225-jet package announced after Turkish President Tayyip Erdogan met U.S. President Donald Trump a year ago. The agreement was held up by Turkish Airlines’ request for an industrial arrangement covering engine maintenance, including a possible Premier facility that would give the airline accelerated access to CFM’s latest repair technology. The deal is back on course and may be signed next week, three of the people said. Boeing and CFM, which is co-owned by GE Aerospace and France’s Safran, declined to comment, while Turkish Airlines did not respond to a request for comment. The carrier operates more than 400 Boeing and Airbus jets and is also evaluating additional regional and long-haul aircraft.