SEOUL: North Korean leader Kim Jong Un replaced several senior officials after a "grave incident" in the country's efforts to defend itself against the coronavirus pandemic, state media reported Wednesday.

Pyongyang closed its borders in January last year to defend itself against the pandemic that first emerged in neighbouring China and has gone on to sweep the world.

It has not publicly confirmed any cases of the disease at any point, neither in state media nor in the test statistics it has disclosed to the World Health Organization.

But officials had "caused a grave incident that poses a huge crisis to the safety of the nation and its people", Kim told a politburo meeting, according to the Korean Central News Agency.

It did not specify any details of what had happened.

But Kim added that the "incompetence and irresponsibility of the senior officials are a major factor that hampers the implementation of important tasks", adding that they were "captivated by selfishness and passivity".

The impoverished, nuclear-armed country is under multiple sets of international sanctions over its nuclear weapons and ballistic missile programmes.

Its ramshackle health system and lack of medical supplies would leave it struggling to cope with a major coronavirus outbreak.

New members of the presidium of the politburo -- the highest decision-making body of the ruling Workers' Party -- and the politburo were named at the meeting on Tuesday, KCNA reported, adding that "government officials were transferred and appointed".