North Korean leader Kim Jong-un attended a fertilizer factory completion ceremony, state media reported Saturday, his first public appearance after 20 days of absence that sparked rumors about his health.

The official Korean Central News Agency reported that Kim cut the tape at the ceremony marking the completion of Sunchon Phosphatic Fertilizer Factory in Sunchon, north of Pyongyang, on Friday.

Photos released by KCNA showed Kim, dressed in a dark Mao suit, cutting the red ribbon during the ceremony and talking to accompanying officials with a smile on his face. They did not show any signs of an illness.

"All the participants broke into thunderous cheers of 'hurrah!' extending the greatest glory to the Supreme Leader who has brought about a new change in the development of Juche-based fertilizer industry and has led the grand revolutionary advance for strengthening self-supporting economy to a victory with his outstanding leadership," KCNA said, referring to the North Korean concept of self-reliance.

"He looked round several places including raw material processing process, yellow phosphorus production process, ammonium phosphatic fertilizer production process, and packing process, being briefed about the production processes of the factory," KCNA added.

Kim was also quoted as expressing "satisfaction about the wonderful creation" and "set forth the tasks and ways for developing our chemical industry in a correct orientation as required by the new century."

  Accompanying Kim were his sister Kim Yo-jong, Pak Pong-ju, vice chairman of the WKP's Central Committee, Premier Kim Jae-ryong and other senior officials, according to KCNA. No. 2 leader Choe Ryong-hae was not among the attendees.

This marked Kim's first public appearance since April 11, when he presided over a Politburo meeting of the ruling Workers' Party.

His absence from an annual event marking the April 15 birth anniversary of his late grandfather and national founder, Kim Il-sung, sparked speculation he might be seriously ill.

Also Saturday, North Korea's state broadcaster Korean Central Television aired Kim's attendance at the fertilizer factory completion ceremony in the first news report of its daily program that began at around 3 p.m.

In the 15-minute broadcast, Kim was seen walking without the support of anyone, waving his hands to the crowd and clapping his hands, moves that apparently aimed at ending rampant speculation about his health.

Leif-Eric Easley, associate professor of international studies at Ewha Womans University in Seoul, said North Korean media reports of Kim Jong-un making a site visit to a fertilizer factory "represent an attempt to signal he is alive and well."

CNN reported last week that the United States is looking into intelligence that Kim is in "grave danger" after surgery. That came after a report by Daily NK, a South Korea-based news outlet specializing in North Korea issues, that Kim was receiving medical treatment following a cardiovascular procedure.

Fanning the rumors further, North Korean media had not provided no report on photo on his public activity, though it carried articles on his routine day schedules such as sending diplomatic letters or sending gifts to honored citizens.

South Korean officials have repeatedly rejected such rumors, saying that no unusual movements have been found in North Korea with regard to Kim's health.

In Washington, US President Donald Trump declined to comment on Kim's reappearance.

"I'd rather not comment on it yet," Trump told reporters at the White House, according to Reuters. "We'll have something to say about it at the appropriate time."

It is not rare for Kim to disappear from public view. The latest absence marked the third time this year alone that Kim has not appeared in public for more than 10 days.

His longest absence from public view was in September 2014, when he disappeared for about 40 days and returned with a cane and limping. Seoul's intelligence agency later said that he had a cyst removed from his ankle.

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

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