North Korean leader Kim Jong-un / Korea Times file

South Korea has seen no unusual signs with regard to North Korean leader Kim Jong-un's health, government officials said Tuesday, after CNN reported that Kim is "in grave danger after a surgery."

CNN cited an unidentified "U.S. official with direct knowledge" but offered no further details.

"There are no unusual signs in North Korea," a government official told Yonhap News Agency on condition of anonymity. "It is not a fact."

Another official said there have been no signs detected with regard to Kim's health, emphasizing that Kim had continued to be seen in public until recently. A spokesperson of Cheong Wa Dae also said that no unusual signs have been detected about Kim's health.

The CNN report came after the Daily NK, a South Korean internet news outlet specializing in North Korea news, reported that Kim has been receiving medical treatment at a villa in the resort county of Hyangsan, outside of Pyongyang, following a cardiovascular procedure.

CNN: North Korean leader 'in grave danger' after surgery 2020-04-21 11:11  |  North Korea
Speculation has arisen about what happened to Kim since he apparently skipped an annual visit to the Kumsusan Palace of the Sun on the occasion of the 108th birthday of his late grandfather and state founder Kim Il-sung last Wednesday.

Kim was last seen on April 11 in state media reports presiding over a political bureau meeting of the ruling Workers' Party on Saturday, calling for "strict national countermeasures to thoroughly check the infiltration of the virus."

He, however, did not attend a major session of the country's rubber-stamp parliament the following day, nor did state media report on his attendance in the country's latest weapons tests last Tuesday, a day before the late founder's birthday, an unusual absence given that he had mostly supervised such firings in recent months.

Kim has reportedly had health problems apparently linked to obesity and heavy smoking. His prolonged absence from public view has often spawned rumors about deterioration in his health.

From early September 2014, he disappeared from the public eye for about 40 days and returned limping. Seoul's intelligence agency later said that he underwent surgery to have a cyst removed from his ankle.

It is extremely difficult to confirm speculations about the reclusive country, with only a small number of insiders privy to such sensitive information about its leader's condition.

On Monday, the North's official Korean Central News Agency reported that Kim sent a congratulatory message to Cuban President Miguel Mario Diaz-Canel Bermudez for his 60th birthday, indicating that he is carrying out state affairs as normal.

Kim took over as leader of the communist state after his father Kim Jong-il died of a heart attack in late 2011. (Yonhap)