North Korean leader Kim Jong-Il, who is reportedly recovering from a stroke, began losing consciousness at work in April and could not properly govern as his health worsened, a major daily Japanese newspaper reported Sunday.
Citing an unnamed Chinese official with close ties to North Korea, the Mainichi Shimbun said the 66-year-old Kim's unspecified condition impaired his judgment, and his decisions related to international denuclearization talks became less flexible.
Kim had often worked late nights but was forced to curtail his schedule starting May or June, the Mainichi said.
In Seoul, Kim Ho-nyeon, a spokesman at South Korea's Unification Ministry, said Sunday that the Mainichi's report could not be confirmed.
An official of the National Intelligence Service, South Korea's spy agency, also said his agency could not immediately confirm the Japanese media report. He asked not to be named, citing internal policy.
Japanese foreign ministry officials were unavailable for comment.
Kim's health noticeably deteriorated last summer when serious kidney and heart problems began to plague the leader, according to the Japanese newspaper.
South Korean media have recently reported that Kim collapsed around Aug. 15. His absence from last week's 60th anniversary celebrations intensified speculation that the leader — long believed to be suffering from diabetes and heart disease — was seriously ill. He had been out of the public eye for weeks and foreign doctors were rumored to have been flown into Pyongyang to treat him.
A separate Japanese report Saturday said Kim underwent heart surgery by a team of German doctors in late April 2007.
It was unclear, however, whether his current condition is connected to the surgery, which was performed to widen blocked arteries, the Asahi Shimbun said, citing an unnamed South Korean government official.
Concerns have emerged that Kim's health could further complicate the six-party disarmament talks, which recently hit a snag over how to verify North Korea's nuclear programs. The negotiations include North Korea, South Korea, Japan, China, Russia and the United States.
South Korea's top nuclear envoy, Kim Sook, told reporters Friday that Seoul officials were discussing the matter with their counterparts in the U.S. and China.
South Korea said recently that North Korea had begun restoring its nuclear facilities, apparently to protest delays by Washington in removing the North from a list of terrorism-sponsoring countries. North Korea stopped disabling its Yongbyon nuclear complex in mid-August.
The U.S. has said North Korea must agree to an international plan to verify the account of its nuclear programs it submitted in June if it wants to be removed from the terrorism list.