SEOUL, South Korea (AP) — The young son and heir apparent of North Korea's leader traveled Friday to neighboring China, news reports said, in a visit to his country's key ally and benefactor that would mark his biggest-yet diplomatic responsibility.
The visit, reported by South Korean media citing unnamed sources, would be a clear signal that the 20-something son of Kim Jong Il is well on his way to becoming North Korea's next ruler after being promoted to a high-profile political post last year. Key defense positions and diplomatic duties had been expected to follow as part of the grooming process.
The reported trip by Kim Jong Un is taking place amid worries about food shortages in North Korea and international pressure on Pyongyang to abandon its nuclear weapons programs. It could be a bid to forge stronger ties with China, which provides crucial food and fuel aid to Pyongyang and is keen to ensure the neighbor's stability.
Kim Jong Un arrived in the border city of Tumen in northeast China on Friday morning, reports said. He was accompanied by Jang Song Thaek, his uncle and a core member of Kim Jong Il's inner circle, South Korea's mass-circulation Chosun Ilbo newspaper said.
Officials at South Korea's Foreign Ministry and the Unification Ministry said they were trying to confirm the trip. There was no mention of the trip in North Korean state media.
China's Foreign Ministry and the Communist Party leadership office that handles relations with North Korea told AP that they didn't know anything about a Kim Jong Un visit. In the past, the Chinese government has only confirmed visits by Kim's father once he has returned home.
Security was tight in Tumen, with more police than usual, the Yonhap News Agency reported, citing an unnamed source in the city. In Mudanjiang, a northeastern Chinese city near the North Korean border that the senior Kim visited last year, security also was high along the streets, the director of the main office of the city's Beishan Park, told The Associated Press. He gave only his surname Liu.
He said provincial Chinese leaders converged Thursday night at a government guesthouse known locally as the VIP Building where visiting dignitaries are entertained.
Though he rarely travels abroad, Kim Jong Il also visited China in August last year, a trip that reportedly included a meeting with China's top leader and an appeal for diplomatic and financial support for the hereditary succession.
Kim Jong Un, who is in his late 20s, made his international public debut in October last year after being promoted weeks earlier to four-star general and receiving the important position of vice chairman of the ruling Workers' Party of Korea's central military commission.
The trip "is North Korea's declaration to the international community of his status as heir," said professor Yoo Ho-yeol, an expert at Korea University. "This also signifies that the succession process inside North Korea is progressing smoothly."
That succession process has been closely watched since the elder Kim, 69, who himself inherited power from his father, reportedly suffered a stroke in 2008. He appears to have recovered and has resumed his steady round of visits to factories and farms around the country.
China and North Korea have a special relationship, with China playing a significant role in both Kim family lore and modern North Korean history.
North Korea founder Kim Il Sung lived in Jilin city in China in the late 1920s, and it was in Jilin that he trained Korean revolutionaries in the fight against colonizer Japan, according to North Korean state media. Kim Jong Il reportedly visited a school in Jilin city during his trip to China last year.
During the Korean War, China sent scores of troops to Korea to help the North Koreans fight U.S.-led U.N. and South Korean troops.
Beijing remains Pyongyang's biggest benefactor, and North Korea increasingly is looking to China for guidance on developing its economy.
A trip to Tumen, "which is the gate for economic cooperation between the two countries, also means that Kim Jong Un will take up a central role in future economic relations with China and use it to build his credibility as a leader," professor Yoo said.
Kim's reported trip comes as the United States and other countries accuse Pyongyang of pushing ahead with its nuclear programs even as its people go hungry.
China is standing by the North, however, blocking the release this week of a report by U.N. experts accusing North Korea of violating sanctions that ban the export and import of ballistic missile and nuclear-related items as well as conventional arms and luxury goods.
North Korea relies on China for more than just diplomatic support. Beijing is also a major supplier of food and other aid.
The U.N. says North Korea needs more than 474,000 tons (430,000 metric tons) of food aid to fend off widespread hunger.
South Korea says it will resume large-scale aid only after North Korea apologizes for last year's deadly sinking of a South Korean warship — which Seoul blames on a North Korean torpedo — and the North's attack on a front-line South Korean island.
Associated Press writers Kay Seok and So Yeon Kwon in Seoul and researcher Zhao Liang in Beijing contributed to this report.