North Korea’s reported appointment of a hard-line figure with a military background as its new foreign minister has heightened uncertainties over the recalcitrant regime’s denuclearization talks with the US and relations with South Korea.

The North last week notified foreign ambassadors based in Pyongyang of its appointment of Ri Son-gwon as the communist state’s top diplomat -- likely to be officially announced this week.

Ri, a former army officer, has been serving as chairman of the Committee for the Peaceful Reunification of the Fatherland, which is equivalent to the South’s Unification Ministry. Known for his tough treatment of South Korean government officials and business leaders, Ri has otherwise little experience in foreign affairs.

He replaces Ri Yong-ho, a seasoned career diplomat who has served as the North’s foreign minister for the past four years.

The replacement, which is described by diplomatic observers here as unreasonable and beyond imagination, comes at a time nuclear talks between Washington and Pyongyang remain stalled with South Korea and the US showing signs of friction over their approach to North Korea.

It is not seen as a signal that Pyongyang will reshape its policy toward Washington.

Rather, the move seems to reflect North Korean leader Kim Jong-un’s frustration with Washington’s firm stance that it will maintain sanctions on his regime until Pyongyang takes substantial steps toward dismantling its nuclear arsenal.

US President Donald Trump’s administration didn’t flinch at Pyongyang’s repeated threats to resume nuclear and long-range missile tests unless Washington made concessions by December.

Early this month, Kim said he saw no reason to stick to his self-declared moratorium on nuclear and long-range missile tests and would show off a “new strategic weapon.”

But he has refrained from turning his threat into action, apparently out of concerns about Trump’s unpredictable response to the North’s new provocation that he might view as undermining US security interests or his own reelection prospects.

In the face of this frustrating situation, Kim might have made an impromptu decision to appoint a hawkish figure to the top diplomat’s post, hoping it might help make a breakthrough in stalled negotiations with the US.

There is no doubt that the appointment will do little to change the position of the Trump administration.

Meanwhile, the appointment makes it clearer that the North will not abandon its nuclear arms, which the totalitarian regime sees as essential to its survival. Kim has repeatedly called on his people to step up efforts to build a self-reliant economy, suggesting he will not swap his nuclear arsenal for sanctions relief.

The replacement may also prompt North Korean officials, including diplomats, to compete to show loyalty to Kim, increasing volatility in the way Pyongyang deals with Washington and Seoul.

The North’s diplomatic bureaucracy has so far remained relatively detached from irrational behavior and adherent to cool-headed calculation. Alarmed by the appointment of a hard-line military figure as their head, North Korean diplomats may change their attitude.

It has yet to be seen whether Pyongyang will make a shift in its stance on inter-Korean matters. One of the barometers will be the reshuffle of the North’s line-up for handling relations with the South.

In recent months, Pyongyang has rejected Seoul’s repeated calls for dialogue on improving inter-Korean ties. It has ridiculed Seoul’s efforts to play a mediator’s role between the US and the North.

This attitude appears to stem from its judgment that President Moon Jae-in’s government in Seoul will not be able to resume inter-Korean projects in violation of US-led international sanctions on the North.

In his New Year’s news conference last week, Moon suggested allowing South Koreans to make individual tours to the North as a way to circumvent the sanctions regime. His new initiative has amplified Washington’s concerns about what it sees as his overeager desire to promote inter-Korean cooperation in the absence of progress in the North’s denuclearization.

Pyongyang may seek to take advantage of Moon’s latest proposal to drive a wedge between Seoul and Washington. Or it may opt to make an unexpected provocation against the South in a bid to heighten pressure on the Moon administration to stay away from Washington in approaches to inter-Korean projects.

Moon and his aides should not let the South Korea-US alliance be further strained by pushing through cross-border projects without paying heed to US calls for prior consultations to prevent such moves from triggering the sanctions mechanism.