ABUJA, Nigeria, (AP) – Nigerian foreign minister is threatening action against Iran if it violated international law and U.N. sanctions in an arms smuggling case.

Nigerian Foreign Minister Odein Ajumogobia told a news conference Friday that Iran’s foreign minister has authorized Nigerian officials to interview one of two Iranians implicated in the arms shipment discovered in a Nigerian port last month. Ajumogobia says the other man has diplomatic immunity. Nigerian authorities believe both men are hiding in the Iranian Embassy.

“If Nigeria finds at the conclusion of the investigation that there has been a breach of international law, a breach of U.N. sanctions, Nigeria is a member of the U.N. Security Council (and) we will do what is necessary,” Ajumogobia said.