South Korean President Moon Jae-in said on Friday engagement with North Korea would only be possible when the South has the security ability to overwhelm the North, the presidential office said in a media briefing.

Moon made the comments during a visit to the state-run Agency for Defense Development, where he watched a test-firing of an indigenously developed ballistic missile, hours after U.S. officials said North Korea has carried out a test of a rocket engine that they believe could be for an intercontinental ballistic missile.