South Korean President Moon Jae-in on Sunday nominated a former navy chief as his defense minister, the president's office said, as the government faces challenges tackling North Korea's rapidly developing weapons program.

The nominee, Song Young-moo, was well suited to deal with North Korea's nuclear and missile threat, the presidential Blue House office said.

Under third-generation leader Kim Jong Un, North Korea has been conducting missile tests at an unprecedented pace in an effort to develop an intercontinental ballistic missile capable of striking the mainland United States.