President Hassan Rouhani on Wednesday said Iran filed the lawsuit with the International Court of Justice (ICJ), vowing that his administration will pursue the case to its end, Press TV reported.
On April 20, the US Supreme Court ruled that about $2 billion in frozen Iranian assets must be turned over to American families of people killed in the 1983 bombing of a US Marine Corps barracks in Beirut.
Tehran has long rejected allegations of involvement in the bombing.
The money confiscated under the US court ruling belongs to the Central Bank of Iran (CBI). The assets were blocked under US sanctions.
Rouhani called the verdict by the American court illegitimate, saying the case of American nationals killed in Lebanon had nothing to do with Iran.
"It is not clear what the Americans were doing in Lebanon and how is the case related to Iran," Rouhani said, adding Tehran will never keep silent on the issue and that legal action will continue until all compensations are retrieved.