In-depth series on GlobalPost: What's next for North Korea?
The visitors went to view Kim Jong Il's body at the Kumsusan Memorial Palace, according to Seoul's Unification Ministry.
Signing their names in the book of condolences, Lee Hee Ho wrote that she hoped the spirit of the North-South Joint declaration would be "carried forward to achieve national reunification as early as possible," the North's state news agency KCNA reported.
It was at the palace that the South Koreans met Kim Jong Un. The exchange lasted only about 10 minutes, according to Seoul officials. The South's government insists that Lee Hee Ho is not carrying any official message for Pyongyang, said the BBC.
Yet the meeting "could be intended to push South Korea to pursue cooperative projects that would give North Korea much-needed aid," the AP said.
The South has banned ordinary citizens from travelling to the North to mourn Kim Jong Il, a decision that Pyongyang's reunification committee said would have "unimaginably destructive consequences for inter-Korean relations," the Chosun reported.
Meanwhile Kim Jong Un was hailed by North Korean state media as the head of the ruling Workers' Party central committee on Monday. The new title means that he now controls "one of the country's highest decision-making bodies," the BBC said.
Kim Jong Un's uncle and mentor, Jang Song Taek, has also been pictured in full military uniform for the first time, confirming his status as a senior general and fuelling speculation that he will act as regent to Kim Jong Il's young successor.
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