Thursday's meeting was the first high-level dialogue between the two Koreas since the delegation returned from the North.
The meeting between Kim Jong Un, leader of nuclear-armed North Korea, and the South's President Moon Jae-in will be only the third of its kind, and will be followed by landmark talks with US President Donald Trump which could come as early as May.
The official Xinhua news agency said Kim paid an "unofficial visit" to Beijing this week and met with President Xi Jinping at the Chinese leader's request. "But, it won't be easy because the U.S.is pressuring North Korea strongly to accept Libyan-model solutions by hiring [the hawkish Mike] Pompeo [as Secretary of State] and others, while Pyongyang will try to resist this".
By reintroducing China, which is the North's only major ally, as a major player, North Korea also gains leverage against South Korea and the United States, analysts say.
Tension over North Korea's tests of nuclear weapons and ballistic missile surged previous year and raised fears of US military action in response to North Korean threat to develop a nuclear weapon capable of hitting the United States.
Pyongyang, too, dispatched a three-person delegation led by Ri Son Gwon, chairman of the Committee for the Peaceful Reunification of the Country (CPRC).
Even more surprising was his pledge to denuclearise the Korean summit.
Adea Shabani: Police find body believed to be missing model
According to her Facebook profile , the 25-year-old graduated from high school in Skopje, Macedonia , in 2010. A native of Macedonia, Shabani moved to the US less than two years ago to pursue an acting career.
"Both sides will continue working level discussions (on the agendas) while focusing on the issues surrounding the denuclearization of the Korean Peninsula, the stabilization of peace and the development relations between the South and North".
The Libyan disarmament issue was resolved in 2003 when then-Libyan leader Muammar Gaddafi agreed to eliminate the Northern African country's weapons of mass destruction program, including a decades-old nuclear weapons program.
On Wednesday, Mr Trump welcomed news of progress following the talks between the Chinese and North Korean leaders in Beijing.
Mr Trump wrote on Twitter he had received a message from Mr Xi on Tuesday night that his meeting with Mr Kim "went very well" and that Mr Kim looked forward to meeting the United States president.
A working-level meeting discussing telecommunication systems used during the summit will be held separately, with a date and venue to be announced later. "There is a good chance that Kim Jong Un will do what is right for his people and for humanity", Trump said on Twitter on March 28. Yang met with presidential national security director Chung Eui-yong on Thursday and is to meet President Moon on Friday. The meeting led to family reunions until ties soured under conservative President Lee Myung-bak.
The Koreas agreed to a summit when Moon's envoys visited Kim in Pyongyang earlier this month.
South Korea said Kim is expected to hold a summit with Trump on denuclearization and normalization of bilateral diplomatic ties by the end of May, after meeting with its president, Moon Jae In, in late April.
About 70 South Korean officials and technicians flew to Pyongyang on Thursday to set up the performance equipment.