"I understand that Chairman Kim told (South Korean) President Moon (Jae-in) during their summit in September that if the US took corresponding steps he would not only be willing to shut down the Yongbyon nuclear facilities but also allow verification", Yonhap quoted the source as saying.
Kim and President Donald Trump held a summit in June and signed a denuclearization deal.
On Sunday, Meari, a North Korean propaganda website, slammed South Korea for joining in the United Nations adoption of the resolution, saying that it runs counter to the improvement of inter-Korean relations.
USA president Donald Trump and Kim Jong Un held a historic summit in Singapore earlier this year, signing a vaguely worded deal on denuclearisation.
"We are facing a moment when we need to decide whether (Kim's Seoul visit) will be better before or after the second North Korea-US summit, which will be more effective in bringing peace and prosperity to the Korean Peninsula", the spokesman added.
After inspections are completed, the train will return to Gaeseong, where a South Korean locomotive will take the train back to Seoul.
Nancy Pelosi wins nomination for Speaker of the House
Steny Hoyer and James Clyburn, were elected by unanimous consent to their respective posts of Majority Leader and Majority Whip. Some are among about a dozen freshmen who had said they want new leadership, but others didn't sign the letter, aides said.
President Moon has also taken steps to ease military tensions with North Korea at the Demilitarised Zone (DMZ) that separates the two Koreas.
Pompeo's North Korean counterpart has been Kim Yong-chol ever since he made his first visit to Pyongyang at the beginning of April as the Central Intelligence Agency director.
But at a meeting with Moon in Paris last month, Azoulay suggested the requests be combined, and the idea was also taken up with North Korean officials.
Once the joint inspections are over, South Korea views that Seoul and Pyeongyang will be able to hold a ground-breaking ceremony, within this year AS PLANNED, . for linking and modernizing their rail and road networks. This step was in response to the US demands that North had to take steps to fully close its nuclear and missile facilities before it agrees for easing of global sanctions. But the DPRK (North Korea) still has all its nukes, all its missiles and all its military forces intact.
Though Kim had previously expressed his willingness to shut down the nuclear site, there were no reports of him agreeing to allow inspectors in to verify the site. Last week, US Defence Secretary James Mattis foreshadowed that the annual joint Foal Eagle war games would proceed next year, albeit "reduced in scope" so as to keep from "being harmful to diplomacy".