The World Court ordered the United States on Wednesday to ensure that sanctions against Iran do not impact humanitarian aid or civil aviation safety.
Judges at the International Court Of Justice handed a victory to Tehran, which had argued that sanctions imposed since May by the administration of U.S. President Donald Trump violate the terms of a 1955 Treaty of Amity between the two countries.
The ruling is likely to have at most limited practical impact on the implementation of sanctions, which Washington is reimposing and tightening after pulling out of a 2015 nuclear deal that Iran signed with world powers.
The court order issued on Wednesday is temporary pending a resolution of Iran's full lawsuit against Washington by the ICJ, something that could take years.
The ICJ is the United Nations' highest court for resolving disputes between nations. Its rulings are binding, but it has no power to enforce them, and both the United States and Iran have ignored them in the past.
Washington argued last month that Iran's request was an attempt to misuse the court and that the 1955 treaty specifically ruled out using courts to resolve disputes.
The treaty was signed long before Iran's 1979 Revolution which turned the two countries into arch foes.