North Korean state media has confirmed that leader Kim Jong-Un is suffering "discomfort".
It is the first comment on his health issues that are believed to be behind his three-week absence from public view.
In an hour-long documentary entitled "Days of guidance for the people" aired yesterday, state television showed a limping Mr Kim visiting a factory outside Pyongyang, South Korea's Yonhap news agency reported.
At one point, the narrator of the documentary said the leader had kept up his field guidance trips "passionately leading the way for his people despite suffering discomfort".
It is highly unusual for state media to report on a North Korean leader's health and the documentary may have been aired to address growing speculation.
The young leader, who is believed to be 30 or 31, has not been seen in public since he attended a music concert with his wife on 3 September.
The documentary was aired before a recording of yesterday's gathering of North Korea's parliament at which Mr Kim was a notable absentee.
The South's permanently primed North Korea rumour mill has been feeding off Mr Kim's extended absence, with reports that he might be suffering from gout, diabetes, or high blood pressure - or all three.
One source told Yonhap that a North Korean medical team had visited Germany and Switzerland for consultations on Mr Kim's health issues.
In a press briefing today, the South's Unification Ministry refused to add to the speculation.
"We are watching with various possibilities in mind, including the rumours about health problems," a ministry spokeswoman said.
The North's Supreme People's Assembly, or parliament, only meets once or twice a year to rubber-stamp budgets or other decisions made by the ruling party.
It has little real power and there is no onus on Mr Kim to attend when it is convened, although yesterday's session was the first he has missed since assuming power three years ago.
