China quietly deferred a request by North Korea for its young leader to visit last month because the Chinese leadership was preoccupied with its once-in-a-decade leadership change and a host of other distractions, two independent sources said. The move also suggests that China, North Korea’s main food and oil supplier, may be seeking an assurance from the isolated state that it drops its nuclear ambitions, one source said, after it ignored warnings from Beijing not to go ahead with a rocket launch in April. Kim Jong-un’s desire to visit China in September was relayed by his powerful uncle, Jang Song-thaek, effectively the second most powerful figure in North Korea, when the latter met Chinese leaders on a visit to Beijing in August. But China discreetly put off the request, which was never publicised, because the Chinese Communist Party has been busy preparing for its five-yearly congress which is scheduled to open on November 8 when leader-in-waiting Xi Jinping is tipped to replace Hu Jintao as party chief. There is no new timetable for Kim’s visit. “Kim Jong-un wanted to come but it was not a convenient time,” a source familiar with China’s foreign policy said, speaking on condition of anonymity. “The diaries of Chinese leaders were full with certain set events they had to attend,” the source said, citing Premier Wen Jiabao’s summit with EU leaders in Brussels in September. “From China’s perspective, he has to come with something positive,” the source said, referring to North Korea dropping threats to conduct a third nuclear test. Impoverished North Korea is under UN Security Council sanctions due to its 2006 and 2009 nuclear tests. Earlier this year, Western powers had expressed concern that North Korea would carry out a third test, but it never took place. North Korean Vice-Foreign Minister Pak Kil-yon told the UN General Assembly on Monday that the country’s nuclear deterrent was a “mighty weapon that defends the country’s sovereignty”. Analysts have said Beijing may be loath to host Kim due in part to North Korea ignoring Chinese warnings against the rocket launch in April. The UN Security Council, of which China is a permanent member, strongly condemned on the failed launch as a violation of council resolutions. Any insistence on Beijing’s part for “something positive”, for instance that North Korea reins in its nuclear ambitions, would indicate that it is holding its alliance with Pyongyang to a tougher test. Former North Korean leader Kim Jong-il, who died in December, made six visits to China from 2004 to last year while Hu was in office (Hu is president until March next year), a period that also saw Pyongyang actively engage in missile and nuclear arms development. The Chinese leadership has also had distractions apart from the party congress. It has had its hands full debating the fate of ambitious politician Bo Xilai, who was expelled from the party last month and faces prosecution for abusing power, taking huge bribes and other crimes. Xi, the incumbent vice president, was recuperating from a bad back and out of the public eye for almost two weeks last month, skipping meetings with foreign dignitaries, including US Secretary of State Hillary Clinton. Another distraction was anti-Japanese protests that erupted across China over disputed islands in the East China Sea. “There were too many things going on. [China] could not host Kim Jong-un,” a source with close ties to Pyongyang and Beijing told Reuters. The source had revealed Kim’s wish to visit. North Korea’s request was relayed through the Communist Party’s international department which deals with foreign political parties. The international department and the Chinese Foreign Ministry were not immediately available for comment as China is on a week-long holiday to mark the Mid-Autumn Festival and National Day.