North Korean leader Kim Jong-un has made his first public appearance in nearly three weeks, following intense speculation that he was seriously ill or possibly dead.

State television showed Mr Kim walking, smiling broadly and smoking a cigarette at what North Korean state media said was the opening of a fertiliser factory in Sunchon, north of Pyongyang.

Rumours about Mr Kim's health had spread since his conspicuous no-show at celebrations for the birthday of his grandfather, the North's founder, on 15 April - the most important day in the country's political calendar.

His absence triggered a series of unconfirmed reports over his condition, while the United States and South Korea insisted they had no information to believe any of the conjecture was true.

Seoul's unification ministry reacted to the report by saying "groundless" speculation about Mr Kim had caused "unnecessary confusion", calling for more careful consideration in future.

Mr Kim's sudden death would have left Pyongyang facing an unplanned succession for the first time in its history and raised unanswered questions over who would succeed him.

Kim Jong-un pictured during his public appearance following speculation about his health

China, the North's key diplomatic ally and main provider of trade and aid, is keen to maintain stability in its neighbour and avoid the possibility of an influx of refugees.

Footage showed Mr Kim in his trademark black suit, waving to hundreds of workers who cheered his appearance and released balloons.

He was flanked by senior officials - including his sister and close adviser Kim Yo Jong - and showed no outward signs of ill health.

At one point he sat in front of a sign that described the event as a factory opening ceremony for 1 May 2020, but his appearance could not be independently verified.

As with previous public appearances during the global coronavirus pandemic, Mr Kim and his entourage were not wearing masks, unlike the crowd of workers at the ceremony.

Analysts said Kim could not appear in public wearing a mask as it would make him appear vulnerable to the North Korean people.

The North has insisted that it has not seen a single case of coronavirus, although experts say that is unlikely.

Mr Kim and his associated did not wear masks, while the crowd in attendance did

Mr Kim's repeated appearances without a mask had led some to speculate that he may have caught the virus.

The North Korean leader had not made a public appearance since presiding over a Workers' Party politburo meeting on 11 April, and the following day state media reported that he had inspected fighter jets.

Daily NK, an online media outlet run mostly by North Korean defectors, had reported that Mr Kim was undergoing treatment after a cardiovascular procedure last month.

Citing an unidentified source inside the country, it said Mr Kim had needed urgent treatment due to heavy smoking, obesity and fatigue.

CNN then reported that Washington was "monitoring intelligence" that he was in "grave danger" after undergoing surgery, quoting an anonymous US official.

Officials in Seoul had consistently downplayed the reports and a presidential security advisor said that Kim was "alive and well" and staying in the eastern resort town of Wonsan.

Analysts say Kim is likely to make another public appearance in the coming days that will be reported by state media.