"There has been no response yet," defence ministry spokesman Moon Sang-Gyun told journalists, adding that preparations were still underway in case the proposed meeting goes ahead.
Seoul's defence ministry on Monday offered rare talks with the North at the Panmunjom truce village on the heavily militarised inter-Korean border.
Separately Monday, the Red Cross in Seoul also proposed a meeting August 1 at the same venue to discuss reunions of families separated by the 1950-53 Korean War.
The twin proposals are the first concrete steps towards rapprochement with the North since South Korea in May elected the President Moon Jae-In, who favours greater engagement with Pyongyang.
If the government meeting goes ahead, it will mark the first official inter-Korea talks since December 2015. Moon's conservative predecessor Park Geun-Hye had refused to engage in substantive dialogue with Pyongyang unless it made a firm commitment to denuclearisation.
Park was engulfed in a massive corruption scandal that resulted in her impeachment and subsequent ouster from office in March.
"There is no deadline," by which Pyongyang has to respond, a South Korea unification ministry official told Yonhap news agency.
Millions of family members were separated by the conflict that sealed the division of the two countries. Many died without getting a chance to see or hear from their families on the other side of the heavily-fortified border, across which all civilian communication is banned.
Around 60,000 members of divided families survive in the South.
Moon, who took power in May, has advocated dialogue with the nuclear-armed North to bring it to the negotiating table and vowed to play a more active role in global efforts to tame the South's unpredictable neighbour.
But Pyongyang has staged a series of missile launches in violation of UN resolutions most recently on July 4 when it test-fired its first ICBM, a move which triggered global alarm and a push by US President Donald Trump to impose harsher UN sanctions.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)