North Korean leader Kim Jong-un, who has made his first public appearance in five weeks, has been treated by "foreign doctors" because of an apparent leg injury, the South Korean ambassador to China said Tuesday. 

North Korea's state media on Tuesday made its first reports of public activity by Kim in more than 40 days, showing photos of the leader with a walking stick. 

Kim "was suffering from problems in his leg and foreign doctors visited North Korea to treat him," Kwon Young-se told lawmakers during an annual parliamentary audit on the South Korean Embassy in Beijing. 

"To my knowledge, North Korean officials had also visited some foreign countries to get consultations about his treatment," Kwon said, citing information he obtained. 

Kim had been absent from public view since Sept. 3, and the North Korean media have unusually acknowledged that he was suffering from bodily "discomfort." 

Kim missed a key national event celebrating the founding of the ruling Worker's Party of Korea on Friday with high-level party and military officials, fueling speculation about his health.   

The photos carried by North Korea's state media Tuesday of "field guidance" activities by Kim, seen smiling, quelled speculation about his whereabouts and status. 

In an unusual public acknowledgment of the difficulty of deciphering what is going on in North Korea, one of the most isolated countries in the world, Kwon told lawmakers, "There is a limit for us in figuring out what is happening in North Korea." 

However, the South Korean Embassy in Beijing has not detected any indication that Kim's grip on power may be fragile. 

"As far as I understand, Kim is firmly in control of the North Korean regime," Kwon told lawmakers. (Yonhap)