RECLUSIVE leader Kim Jong Il has pancreatic cancer, it was reported.

Seoul's news channel network YTN television said Kim, 67, was diagnosed with the cancer around the time he was felled by a stroke last summer.

The report cited unidentified intelligence officials in South Korea and China.

Kim's health is a focus of intense media speculation due to concerns about instability and a power struggle if he were to die without naming a successor.

His third and youngest son, Kim Jong Un, has widely been reported as being groomed as heir, but the regime has made no announcement to the outside world.

The report cited the officials saying the disease was "threatening" Kim's life.

Pancreatic cancer is usually found in its final stage and considering Kim's age, he is expected to live no more than five years, the report says.

South Korea's spy agency said it could not confirm the report.

The claims came after Kim made a rare public appearance last week, in an annual memorial for his late father and North Korea's founder, Kim Il Sung.

Television footage showed him markedly thinner and with less hair at only the second state event he has attended in person since the reported stroke.

He also limped slightly and the sides of his tight-lipped mouth looked imbalanced in what were believed to be the effects of a stroke.