North Korea’s leader Kim Jong-un has invited South Korea’s President Moon Jae-in to Pyongyang.
It would be the first summit in more than a decade between Korean leaders.
Mr Moon said the Koreas should “make it happen” and encouraged the north to return to negotiations with the US.
The handwritten invitation was delivered by Mr Kim’s influential sister, Kim Yo-jong, at a landmark meeting in the presidential palace in Seoul, as the Winter Olympics opened.
Ms Kim and the North’s ceremonial head of state Kim Yong-nam made up the most senior delegation from the North to visit the South since the Korean War in the 1950s.
The figures from the two Koreas shared kimchi (Korean pickled cabbage) and soju rice liquor, and spoke for three hours.
Ms Kim invited Mr Moon to visit “at the earliest date possible”, a spokesman for South Korea’s presidential palace said.
According to a tweet by the Washington Post’s Tokyo bureau chief, Ms Kim left a note at the palace expressing hope that “Pyongyang and Seoul will become closer in the heart of Koreans” and for “unification and prosperity in the near future”.
How will the US react?
The meeting comes after the US warned against engagement with Pyongyang.
The Trump administration is cautious of Seoul falling for North Korea’s charm offensive during the Winter Olympics, which are taking place amid tension over Pyongyang’s nuclear programme.
Correspondents say the invitation puts Mr Moon in a difficult position as he campaigned on a promise to engage with the North, but his moves in that direction go contrary to the wishes of his US ally
Earlier, US Vice-President Mike Pence briefly encountered Kim Yong-nam at the Games but the two tried to avoid directly facing each other, Yonhap news agency reports.
At the opening ceremony for the Games, Mr Pence, Kim Yo-jong and Kim Yong-nam were seated in close proximity to each other.
Mr Pence stayed seated when the athletes of the host nation marched into the arena alongside those from the North.
On Saturday, he tweeted that the US would not “allow the propaganda charade by the North Korean regime to go unchallenged on the world stage”.