washington libyan prime minister fayez al-sarraj say thursday hopeful u.n.-imposed arm embargo would partially lift branch country military libyan government allow import weapons relate materiel approval u.n. security council committee oversee embargo impose 2011 ... hope embargo partially end least military branch presidential guard coast guard sarraj head government national accord gna say meet u.s. defense secretary jim mattis pentagon speak translator president donald trump host sarraj white house friday talk counterterrorism cooperation ways expand bilateral engagement north african country turmoil since muammar gaddafi downfall give space islamist militants smuggle network send hundreds thousands migrants europe political military fracture leave country mire conflict rival parliaments governments vie power libya eastern-based military commander khalifa haftar align government parliament eastern libya reject u.n.-backed government national accord base capital tripoli gradually strengthen position grind libyan pm sarraj hop ease arm embargo