But in a sign Kim Jong-un is unlikely to give up his nuclear arms, he used the day before the Olympics to host a massive military parade which included trucks carrying intercontinental ballistic missiles - weapons that could potentially strike the United States mainland.
The U.S.is ready to engage in talks about North Korea's nuclear program even as it maintains pressure on Kim Jong Un's regime, the Washington Post reported, citing an interview with Vice President Mike Pence.
The statement from the Ministry of Unification came after the North Korean delegation concluded its three-day visit which included an invitation for South Korean President Moon Jae-in to travel to Pyongyang for talks. Wearing a black coat and with her hair pulled back, she presents a marked contrast to the ceremonial head of North Korea's government - the often expressionless Kim Yong Nam, 90.
The two Koreas have been divided since the conflict ended in a ceasefire in 1953, and the democratic South has risen to become the world's 11th-largest economy, while the North has stagnated under the Kim family's rule.
South Korea's Unification Ministry spokesman Baik Tae-hyun told a regular briefing Seoul was still in close consultations with the United States over its North Korea policy.
"(The visit) shows that North Korea has a strong will to improve inter-Korean relations and that Pyongyang can make unprecedented and bold measures if deemed necessary", the ministry said. They were stopped and most were killed near the palace, which was newly rebuilt in 1991.
The North Koreans and Moon were watching the Koreas' unified women's ice hockey team's first match against Switzerland as it began late Saturday.
On Wednesday, Pence announced the "toughest" round of sanctions yet targeting North Korea at a news conference alongside Japan's Prime Minister Shinzo Abe.
Members of the delegations exchanged greetings during Friday's openg cerermony.
She verbally conveyed Kim's invitation to Moon "to visit the North at his most convenient time", he added.
Any meeting would represent a diplomatic coup for Moon, who swept to power a year ago on a policy of engaging more with the reclusive North and has pushed for a diplomatic solution to the standoff over North Korea's nuclear and missile program.
"In the midst of all this, he ran a military parade that highlighted his ballistic missiles".
Pyongyang conducted its largest nuclear test previous year and in November tested its most advanced intercontinental ballistic missile that experts said has the range to reach anywhere in the United States.
The recent detente, anchored by South Korea's hosting of the Winter Olympic Games, came despite an acceleration in the North's weapons programme past year and pressure from Seoul's allies in Washington. Pence carried a similar message during his trip to Japan and South Korea. It was built in the 1960s under the government of late anti-communist dictator Park Chung-hee as a luxury facility for US troops stationed in South Korea.
The United States may be looking more favourably at diplomatic engagement with North Korea, possibly holding dialogue, as South Korea pushes forward with plans to establish grounds for a rare summit between the two Koreas. They also made plans to attend a concert together on Sunday, to see a North Korean orchestra perform in Seoul.
North Korea agreed to participate in Pyeongchang after Games host South Korea and the International Olympic Committee encouraged the reclusive, heavily sanctioned state to participate as a gesture of peace.