A North Korean delegation led by the cabinet minister for international trade is visiting Iran, the North’s official media says in a rare public report of an exchange between the two countries believed to have secret military ties. The minister for external economic relations, Yun Jong Ho, left Pyongyang on Tuesday by air leading a ministry delegation to visit Iran, the North’s KCNA news agency says. It gives no other detail. North Korea and Iran have long been suspected of cooperating on ballistic missile programs, possibly exchanging technical expertise and components that went into their manufacture.