Choe Son-hui becomes North Korea's first female foreign minister

North Korea has appointed veteran diplomat Choe Son-hui as its first female foreign minister as Pyongyang pushes ahead with a blitz of sanctions-busting weapons tests and ignores US calls for talks.

Choe, who formerly served as the North's vice foreign minister, was tapped to lead the foreign ministry at a ruling party meeting overseen by leader Kim Jong Un, the state media KCNA reported on Saturday.

She replaces Ri Son Gwon, a hardline former military official who previously led talks with the South.

The appointment comes as the United States warned this month that North Korea is preparing to conduct a seventh nuclear test, and says it will again push for United Nations sanctions if that happens.

Kim vowed on Friday that he would use "power for power" to fight threats to the country's sovereignty, but did not mention a nuclear test and offered no details about how he would bolster military power.

"The right to self-defence is an issue of defending sovereignty, clarifying once again the Party's invariable fighting principle of power for power and head-on contest," state agency KCNA quoted Kim as saying in a meeting of the Central Committee of the Workers' Party of Korea.

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Nuclear negotiator to foreign minister

A career diplomat who speaks fluent English, Choe served as a close aide to Kim during nuclear talks with the United States and accompanied the North Korean leader to summits with then US president Donald Trump.

She held a rare question and answer session with reporters on the night the two leaders' summit in Hanoi collapsed without a deal in February 2019, blaming Washington for the failed talks.

"I think the United States has missed a golden opportunity with its rejection of our proposals," she said.

Diplomacy between Pyongyang and Washington have since stalled, with the Kim regime in recent months not responding to the United States' repeated offers to return to negotiations.

The nuclear-armed North has meanwhile carried out a blitz of sanctions-busting weapons tests this year, including firing an intercontinental ballistic missile at full range for the first time since 2017.

South Korean Defence Minister Lee Jong-sup and US Defence Secretary Lloyd Austin on Saturday condemned the North's ongoing military activities and preparations for a nuclear test as unacceptable provocations.

Meeting on the sidelines of a security conference in Singapore, Lee and Austin "agreed to expand the scope and scale of South Korea-US combined exercises," South Korea's Defence Ministry said in a statement.

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