Watchdog American Oversight is suing for documents it believes could illustrate the full scope of white supremacist activity and ideology among troops.
Foreign ministers will meet in Bucharest, where, 14 years ago, the alliance decided to allow Ukraine and Georgia to join over vehement Russian objections.
Monday's developments mark the latest complication in more than 10 years of pretrial hearings for a Saudi accused of organizing the 2000 attack on the USS Cole.