When North Korea on Thursday conducted a test of its most ​powerful intercontinental ballistic missile to date, South Korea’s Defense Ministry was busy with another urgent task: making plans to move.

Earlier this month, South Korea’s president-elect, Yoon Suk-yeol, announced plans to move the Defense Ministry to another building in Seoul so that his presidential office could move into the ministry’s current headquarters by May 10, the day of his inauguration.

The ministry was caught off guard by Yoon’s decision, which came at a time when North Korea is rapidly escalating tensions on the Korean Peninsula. North Korea has often used presidential transitions as an opportunity to make a show of force. This year, the confusion created by Yoon’s plan to relocate both the presidential office and the Defense Ministry could add to the South’s security concerns, analysts said.