The decision puts back on track agreements that would have the three men plead guilty in exchange for being spared the possibility of the death penalty.
U.S. officials are also continuing their search for Austin Tice, an American journalist and Marine Corps vet who disappeared 12 years ago near Damascus.
Nasrallah, who led Hezbollah for more than three decades, is by far the most powerful target to be killed by Israel amid weeks of intensified fighting.