The NEW START, or Strategic Arms Reduction Treaty, was designed to curb the nuclear arms held by both nations. But a proposal to extend the deal by Russia has been rejected by the United States.

Tensions have escalated on the Korean Peninsula after Pyongyang blew up its liaison office with the South and prompted the resignation of South Korea's Unification Minister, a point man designated to mend fragile ties with the North.

The North Korean leader emphasizes the need for the country — which is under harsh international sanctions — to achieve a self-sufficient economy.

North Korea denies Donald Trump's claim that Kim Jong-un has recently sent a letter to the US president.

South Korean President Moon Jae-in says he is making efforts to arrange a visit by North Korea’s leader Kim Jong-un to Seoul, citing a “desperate need” for both sides to improve relations.

North Korean leader Kim Jong-un ends two years of a moratorium on nuclear and missile tests, saying that Pyongyang will soon develop a “new strategic weapon.”

The official North Korean news agency says Pyongyang has carried out a “successful test of great significance” at its space launch center.