Last month's incident has the potential to inflame tensions with a U.S. ally on the war on terror. Officials say the two officers are no longer in the country.
Congress has ordered the FAA to create new rules to safely integrate drones into U.S. airspace by 2015, but North Dakota's farmers aren't waiting.
The pact calls for the "immediate cessation of hostilities." The world's youngest country has been roiled by ethnic violence since December. Thousands have been killed and 1.3 million are displaced.