During a parliamentary interpellation session, Chung said that past experiences show that "unilateral goodwill" alone cannot resolve problems between the two Koreas. That appears to mean Pyongyang should first soften its stance.
Earlier Thursday, South Korea formally offered North Korea dialogue to discuss ways to resume operations at a jointly run factory complex in the North's border city of Kaesong, warning that it would take "grave" measures unless Pyongyang accepts the offer.
"As we proposed dialogue, we hope North Korea will respond" positively, Chung said.
Early this month, North Korea withdrew all of its 53,000 workers from the zone, forcing the 123 small-scale South Korean factories there to suspend their operations. Pyongyang also threatened to permanently shut down the complex, the last-remaining symbol of inter-Korean rapprochement.
Kaesong's suspension was one of a string of measures that the North has taken in anger over U.S.-involved military drills in South Korea and a new U.N. Security Council resolution adopted against its third nuclear test in February.
Chung said it was unclear whether the North used plutonium or enriched uranium for its latest nuclear test. He said the possibility of Pyongyang conducting yet another nuclear test remains open, though there are not clear signs yet.
The North's nuclear test gave rise to calls for South Korea to arm itself with atomic weapons, but Chung voiced opposition to the idea.
"While not pursuing independent nuclear sovereignty, I think (South Korea) can deter (the North's) nuclear programs by managing the extended deterrence provided by the United States," Chung added. (Yonhap)