The powerful sister of North Korean leader Kim Jong Un said her country will never see South Korea as a partner for diplomacy

Since taking office in a snap election in June, the liberal Lee has taken steps to lower tensions with the nuclear-armed North, and the issue is one where he is expected to find common ground with Trump, who still boasts of his historic summits with North Korean leader Kim Jong Un.

North Korean leader Kim Jong Un stressed his order of a quick expansion of his forces' nuclear capabilities, citing the annual U.S.-South Korea military exercises, according to the country's state media.