"It would be unwise, for example, for a new South Korean president on May 10th, presumably in the aftermath of more North Korean provocations and possibly a sixth nuclear test, to declare that he or she is reopening the Kaesong industrial complex," he said.

The factory park, which combines South Korean capital and North Korean labor, used to be a symbol of inter-Korean reconciliation.

South Korea shut down the complex last year in the wake of the North's nuclear and missile tests amid criticism it provides hard currency for the North's weapons program.

Cha said all leading candidates appear to espouse views calling for more engagement with the North.

"They will be in a position where their primary ally, the United States is not of a similar mind. Neither is the partner across the sea, Japan, and arguably China's not in that position, as well," he said. "While I don't think engagement is necessarily completely wrong with North Korea, now is not the time." (Yonhap)