President Moon Jae-in plans to send a special envoy to reciprocate the visit to the South by Kim Yo Jong, the sister of North Korean leader Kim Jong Un during the PyeongChang Olympic Games.
NIS chief Suh is noted for his role in arranging two landmark inter-Korean summits, in 2000 and 2007, and has played a key role in various inter-Korean negotiations, communication and cooperative projects.
The 10-member group will also include Vice Unification Minister Chun Hae-sung, who has been working at the center of the inter-Korean conversations since January.
Yonhap reported Saturday that Han Tae-song said in a Geneva conference last Tuesday that the North's nuclear weapons are a means of protecting its sovereignty and national security against the "harsh hostile policy and nuclear threat of the U.S".
It further said the military drills between the US and South Korea would harm reconciliation efforts and the North shall be "forced" to counter the US.
In response, Moon called for joint efforts to foster an "environment" for an inter-Korean summit, which would mean progress in denuclearization efforts and the North Korea-U.S. relations.
"In decadeslong history of the DPRK-U.S. talks, there had been no case at all where we sat with the U.S. on any precondition, and this will be the case in future, too", the spokesperson said. Moon has yet to accept Kim's invitation to visit Pyongyang.
Regarding U.S. President Donald Trump's remarks on possibly adding stronger sanctions on the North, including a naval blockade, the commentary said Washington is "raging with lunacy for a clash amid the the continued easing of the atmosphere on the peninsula".
The younger Kim made a three-day visit to South Korea to attend the Winter Olympics last month.
Pyongyang has rejected any preconditions and maintains a hardline stance toward the United States administration.
But the South Korean president responded by stressing the importance of having the right "conditions" for talks, suggesting a step towards denuclearisation demanded by Washington.
"You can't expect them to produce any major agreement with this trip alone, but maybe they could at least discuss ways to stop the North from conducting any more ICBM tests", he said. "They've drawn a red line here and it is to never let North Korea build a nuclear-tipped missile to hit America".