washington u.s. president donald trump speak separately friday saudi arabia crown prince mohammed bin salman unite arab emirates crown prince sheikh mohammed bin zayed al-nahyan qatar emir sheikh tamim bin hamad al-thani white house say statement trump tell unity among washington arab partner essential promote regional stability counter threat iran statement say president also emphasize countries must follow commitments riyadh summit defeat terrorism cut fund terrorist group combat extremist ideology say trump also speak qatar al-thani thursday trump tell news conference thursday would will step mediate dispute among u.s.-allied arab state qatar say think deal could come quickly saudi arabia uae egypt bahrain cut diplomatic trade link qatar june suspend air ship rout world big exporter liquefy natural gas home region big u.s. military base nations say doha support regional foe iran islamists charge qatar leaders deny trump speak leaders saudi arabia uae qatar