TOKYO (AFP) - North Korean leader Kim Jong-Il may have had a second stroke in October that has affected his speech, a Japanese news report said Tuesday. US intelligence received information that Kim, 66, had another stroke in late October, Tokyo Broadcasting System (TBS) said on its website, citing an unnamed American intelligence source based in South Korea. According to the information, Kim was receiving treatment at an exclusive Pyongyang hospital for a first stroke he suffered in mid-August, TBS said. "However, he had the second stroke in late October, which caused him difficulty moving his left hand and leg, and has affected his speech," TBS said. The US source, however, was not clear about the severity of the symptoms, TBS said. A South Korea unification ministry spokesman said he had no information to confirm the TBS report. Kim's health is the subject of intense speculation because he has not publicly nominated a successor to run the impoverished and nuclear-armed nation. French brain surgeon Francois-Xavier Roux, head of neurosurgery at the Sainte-Anne Hospital in Paris, has admitted to visiting Pyongyang last month but denied treating the North Korean leader. Meanwhile, the brother-in-law of North Korea's Kim Jong-Il has become even more powerful since Kim fell sick, officials and analysts say, with some believing he is effectively standing in for the supreme leader. The influence of Jang Song-Taek has become greater than ever since Kim was reportedly hit by a stroke, Cheong Seong-Chang, of South Korea's private Sejong Institute think-tank, said Tuesday. "Jang is apparently in charge of receiving orders from Kim and channelling them (to state agencies)," he told AFP. A senior South Korean intelligence official went further, saying Jang was acting like a stand-in in day-to-day state affairs. Kim, the absolute ruler of his hardline communist state, has never publicly designated a successor to run his impoverished but nuclear-armed nation. North Korean state media have recently issued a series of photos of Kim, in an apparent attempt to end speculation about his health. But they have all been undated. The intelligence official, speaking on a radio talk show Monday on condition of anonymity, said Jang, 62, is now in full charge of the security and police agencies including the dreaded secret police. He said Jang has a range of contacts within both the ruling party and the military. "Based on these facts, intelligence authorities here suspect Jang is acting like a stand-in for the chairman." The official added: "We find it rather fortunate that Jang Song-Taek, not the military, is in effect governing the North." Analysts said Jang's new powers do not necessarily mean he is in line to take over. Cheong of the Sejong Institute did not believe he is acting as a stand-in and said the extra powers could easily be taken away depending on the state of Kim's health or on a whim. "It's better to say Chairman Kim is ruling through Jang than Jang is ruling the North," former unification minister Chung Se-Hyun said Tuesday. Baek Seung-Joo of the Korea Institute for Defence Analyses said Jang's influence would likely grow as Kim ages further and his health worsens because relatives would limit access to the leader. Baek told AFP Jang's rise in power would benefit the leader's eldest son Kim Jong-Nam. "There is an axis of alliance between Jang, Kim Kyong-Hui and Kim Jong-Nam," he said. But many analysts believe there will never be another all-powerful dynastic ruler, although a son could head up a collective leadership. Cheong said that if Kim Jong-Il dies suddenly, there would be a power struggle through which a collective leadership from the party elite would likely emerge. "Even if Kim dies suddenly, that does not mean the collapse of a control tower in the North," Cheong said.