Reclusive North Korean leader Kim Jong-Il held talks with President Hu Jintao Monday centred on nuclear issues days after the United States cited intelligence that Pyongyang had atomic bombs, reports said.
Kim and a 30 to 40-strong entourage arrived for the unannounced four-day visit to the Chinese capital by train amid tight security, disembarking ahead of Beijing Station for security reasons, South Korea's Yonhap news agency said.
The agency said the talks took place over lunch at Zhongnanhai, the residence of China's top leaders, and focused on the nuclear stand-off, China's economic assistance to the North and the Stalinist state's economic reform.
Hu briefed Kim on Washington's position on the nuclear issue following his meeting last week in China with US Vice President Dick Cheney, and listened to Kim's ideas on how to end the dispute, unnamed sources were cited as saying.
China declined to confirm the visit, saying it had "no official information".
North Korean embassy staff also refused to confirm Kim was in Beijing.
Japanese leaders, including Prime Minister Junichiro Koizumi, were tight-lipped about the reports of Kim's unannounced trip.
"Neither the Chinese side nor the North Korean side has made any announcement. I'd better not say this or that at a time when it is not confirmed," he told reporters at his official residence late Monday.
There was no special security in place outside the North Korean embassy, with the usual two guards at the entrance, who also denied any knowledge of Kim's visit.
Analysts said Kim would try and persuade China to stay on-side in its long-running spat with the United States over its nuclear weapons programs.
"North Korea will want to persuade China to stay onside and on message," said Paul Harris, an expert in north Asian issues at Hong Kong's Lingnan University.
"Kim also wants more economic aid, but most of all he wants to persuade China that there can be a compromise without resorting to America's demands."
Washington demands the complete, verifiable, and irreversible dismantling of North Korea's nuclear programs, both plutonium and enriched uranium schemes, before it will offer concessions to the impoverished state.
Pyongyang's rulers deny they have a uranium-based program.
For its part, China will want a commitment from North Korea that it will not resort to any radical actions.
"I suspect China will say to Kim - how many bombs do you have? This is China's main concern. It doesn't want the nuclear issue out of hand and an arms race in Asia," said Harris.
A new round of talks is scheduled to take place before the end of June. Kim last visited China in January 2001 on a trip that included a tour of Shanghai's stock exchange. On that trip and a later trip to Russia in 2002, the reclusive leader travelled by train.
It is his third visit to China, the North's closest ally, as leader of the isolated regime.