Sullivan’s comments came as foreign governments have airlifted hundreds of their diplomats and other citizens to safety as the country has spiraled into chaos amid fierce fighting between Sudan’s two rival generals vying for control of the country.

In dramatic evacuation operations, convoys of foreign diplomats, civilian teachers, students, workers and families from dozens of countries wound past combatants at tense front lines in the capital of Khartoum to reach extraction points. Others drove hundreds of miles to the country’s east coast. A stream of European, Mideast, African and Asian military aircraft flew in all day Sunday and Monday to ferry them out.

U.S. special operations forces carried out a precarious evacuation at the U.S. Embassy in Sudan on Sunday, sweeping in and out of the capital with helicopters on the ground for less than an hour. No shots were fired and no major casualties were reported.

Sullivan reiterated that the administration continues to look at “every conceivable option” to help Americans get out of Sudan but is not considering peacekeeping troops.

“It is not standard practice for the United States to send in the U.S. military” into warzones to extract American citizens, Sullivan said “We didn’t do it in Libya. We didn’t do it in Syria. We didn’t do it in Yemen, and no we didn’t do it in Ukraine. Afghanistan was a unique case involving the end of the 20-year war that the United States was centrally involved in.”

An estimated 16,000 private U.S. citizens are registered with the embassy as being in Sudan. The figure is rough because not all Americans register with embassy or say when they depart.

Sullivan said the U.S. “will go to great lengths to support and facilitate” the departure of Americans but also noted that the State Department has been cautioning Americans in Sudan to leave the country for years.

He added, “Americans are free people. We cannot dictate where they travel, tell them they must go or not go to a particular place.”