South Korean President Lee Jae Myung said North Korea continues to produce nuclear material at a pace that could allow it to add up to 20 nuclear weapons a year, underscoring concerns that Pyongyang has no intention of slowing its nuclear program.

North Korean leader Kim Jong Un has dismissed a vice premier over troubles in a factory modernization project, an apparent move to tighten discipline among officials and push them to deliver greater results ahead of a major political conference.