Image:-North Korean leader Kim Jong Un attends the completion of a fertiliser plant
The KCNA report has not been independently verified by Reuters.
At the ceremony on Friday KCNA said Kim cut a ribbon and those attending the event "burst into thunderous cheers of 'hurrah! 'For the Supreme Leader ...' Kim was seen smiling in photographs and talking to assistants at the ribbon-cutting ceremony, as well as touring the plant. The authenticity of the photographs, published on the official Rodong Sinmun newspaper website, was not verified.
Many in the large crowd of people, described as army officials, the ruling party and the community that worked on the project, wore face masks and stood some distance from the podium where Kim and his assistants took part in the ceremony.
North Korea has not reported any coronavirus cases, and has stated that it has taken tough measures to prevent an outbreak. The suggestion he may have been taking precautions against coronavirus was one reason for Kim's absence.
Kim was accompanied by senior officials from North Korea, including his younger sister Kim Yo Jong and top assistant vice-chairman Pak Pong Ju of the State Affairs Commission and Cabinet Premier Kim Jae Ryong, and KCNA said.
When asked about the KCNA report on Kim, U.S. President Donald Trump said: "I don't want to comment on it yet." "We'll have to say something about it at the right time," he told reporters at the White House.
Speculation about Kim's health was rife after he missed state founder Kim Il Sung's birth anniversary celebrations on April 15. The day is a major North Korean holiday, and Kim as the leader usually pays a visit to the mausoleum where his grandfather is in state.
He last made a public appearance at a meeting of the ruling Workers' Party Politikburo on April 11.
A South Korean news outlet specializing in the North reported that Kim was recovering after a cardiovascular procedure after his absence from the anniversary. It followed a flurry of other unconfirmed reports about his condition and whereabouts.
South Korean and U.S. officials expressed skepticism about the reports.
State TV footage on Saturday showed Kim's stiff and jerky leg movements and one of the pictures showed in the background a green golf cart, similar to one he used in 2014 after a long public absence.
"Preparing desks and chairs on stage seemed a bit rare for such an outdoor occasion," said of the ceremony Nam Seong-wook, a professor of North Korean studies at the University of Korea.
"Kim may have some physical conditions that prevent him from standing too long and he needs to sit down after standing up for a while." Nam said that if Kim is unable to stand for long periods, he may not have attended the anniversary event in April at the Kumsusan Sun Palace, where he would have had to stand for at least an hour.
The town of Sunchon where the fertilizer factory was built is about 50 km (30 miles) north of Pyongyang in the western region, away from Wonsan, the eastern coastal resort where officials from South Korea and the U.S. said Kim may have stayed.
Satellite images showing a train usually used by Kim near the resort of Wonsan, as well as boats frequently used by Kim and his entourage, suggested he might stay there.
Officials in South Korea and the U.S. said Kim may be there to avoid coronavirus exposure, and expressed skepticism about media reports that he had some sort of serious disease.
The former top U.S. diplomat for East Asia, Daniel Russel, said it would take time to assemble pieces of the puzzle of Kim's disappearance.
His reappearance showed that authoritative information about a North Korean leader's well-being and whereabouts was carefully guarded, and rumors about him needed considerable skepticism, Russel said.
However, the rumors had served to focus attention on the succession plan for North Korea, which "is filled with risk in a monarchical and cult-like dictatorship, and the absence of a designated adult heir compounds that risk many times over," Russel said.
Earlier, a source familiar with U.S. intelligence analyzes and reporting said U.S. agencies believed that Kim Jong Un wasn't ill and remained in power for much.
"We believe he is still in charge," said the source on condition of anonymity.
The source had not been able to confirm the KCNA report immediately.
POSSIBLE CORONAVIRUS PRECAUTIONS
South Korean Unification Minister Kim Yeon-chul, who oversees Pyongyang's engagement, said it was plausible that Kim was absent as a precaution over the coronavirus pandemic, in view of the stringent steps taken to stem an outbreak in the country.
Harry Kazianis, senior director of Korean studies at Washington's think-tank Center for the National Interest, said this could still be the case.
"The most likely explanation for Kim's absence is to declare the coronavirus pandemic an existential threat to North Korea ... He most likely took steps to ensure his health, or was personally affected by the virus in some way, "Kazianis said after the KCNA report.
The reported appearance of Kim at a fertilizer plant is the latest signal to domestic audiences that he is watching for their economic and food well-being, but nuclear analysts believe it is likely to be part of the efforts to enrich covert uranium in the North.
A recent report by the James Martin Center for Nonproliferation Studies in Monterey, California, provides strong evidence of the involvement of the Sunchon phosphate fertiliser plant in uranium extraction, pointing to its dual-use.
Negotiations to dismantle North Korea's nuclear and missile programs were stalled in late 2019.