Abdella Ahmad Tounisi was arrested at a Chicago airport in 2013 trying to board a flight for Turkey. Prosecutors say he hoped to join Nusra Front militants.
Tounisi earlier pleaded not guilty to attempting to provide material support to a terrorist group. Tounisi is scheduled to change his plea Tuesday at a hearing in U.S. District Court in Chicago after several weeks of talks between his lawyer and federal prosecutors.
Terms of a plea deal between Tounisi and the government haven't been disclosed. Prosecutors typically agree to recommend lower sentences if defendants agree to plead guilty.