The U.S. on Monday urged the United Nations' highest court to toss out a case filed by Iran that seeks to recover around $2 billion worth of frozen assets the U.S. Supreme Court awarded to victims of a 1983 bombing in Lebanon and other attacks linked to Iran.

The case at the International Court of Justice is based on a bilateral treaty that the Trump administration terminated last week. Despite that, the United States sent a large legal delegation to the court's headquarters in The Hague to present their objections to the case, which Tehran filed in 2016.

U.S. State Department lawyer Richard Visek told the 15-judge panel that U.S. objections to the court's jurisdiction and admissibility "provide a clear basis for ruling that this case should not proceed to the merits."

Visek said the case is based on "malicious conduct" by Iran, a country Washington has long classified as a state sponsor of terrorism around the world. Iran denies that charge.

"At the outset we should be clear as to what this case is about," Visek said. "The actions at the root of this case center on Iran's support for international terrorism and its complaints about the U.S. legal framework that allows victims of that terrorism to hold Iran accountable to judicial proceedings and receive compensation for their tragic losses."

The attack at the heart of the case was a suicide truck bombing of a U.S. marine barracks in Beirut in October 1983 that killed 241 military personnel and wounded many more. A U.S. court ruled that the attack was carried out by an Iranian agent supported by the Hezbollah militant group.

In 2016, the U.S. Supreme Court ordered some $2 billion in assets of Iran's state bank that had been frozen in the United States to be paid as compensation to relatives of victims of attacks including the Beirut bombing.

"Iran's effort to secure relief from the court in this case - to in effect deny terrorism victims justice - is wholly unfounded and its application should be rejected in its entirety as inadmissible," Visek told judges, saying that the dispute did not fall into the 1955 Treaty of Amity cited by Tehran as the basis for the court's jurisdiction.