The ruling opens the way for the court to now hear Iran’s case on its merits, which news reports suggest, given the complexity of the case, could take several years. Iran filed the case in 2016, based on the 1955 Treaty of Amity between the two nations, from which the US later unilaterally withdrew, in 2018.

The case revolved around assets seized from the Iranian national bank, Bank Markazi, which were taken by the US to compensate victims of a 1983 suicide bombing of a Marine Corps base in Beirut, Lebanon, which the US blames on Tehran. Iran denies involvement in the attack which killed more than 300, injuring many more, most of whom were US military personnel.

The US has argued that Iran’s claims to retrieving its assets based on the Treaty of Amity, were now void, following the US decision to withdraw.

In an 11-4 majority ruling on Wednesday, the ICJ upheld one of five US objections, in this instance to the Court’s jurisdiction, based on Iran’s assertion of State immunity, but the judges unanimously rejected the US argument that measures freezing Iranian assets fell outside the scope of the treaty.

The judges also unanimously rejected the US claim that the case was an abuse of process, and that it should be thrown out due to Tehran’s “unclean hands”, the US having cited Iran’s alleged sponsorship of terrorism and alleged ambitions to develop nuclear weapons.

ICJ President Abdulqawi Yusuf, reading the ruling, said that the panel “unanimously finds that it has jurisdiction…to rule on the application filed by the Islamic Republic of Iran on 14 June 2016.”