(JTA) — A defamation lawsuit against an anti-Iran advocacy group was dismissed for national security reasons.

On Thursday, a federal court judge in New York tossed the private lawsuit by the Greek shipping magnate Victor Restis against United Against Nuclear Iran. Restis initiated the suit two years ago after the group accused him of fronting for Iran’s government in its bid to bypass energy sector sanctions aimed at stopping the country’s alleged nuclear weapons program. He denies the claim.

The U.S. Attorney’s Office claimed that the litigation could give away state secrets.

The judge, Edgardo Ramos, agreed in his decision that there was “a reasonable danger that disclosure of the facts underlying the government’s assertion would in fact jeopardize national security.”

The decision was unusual, as the United States was not a party to the lawsuit.