"It is very regrettable that the North unilaterally postponed the reunions, with just four days left," Unification Ministry spokesman Kim Eyi-do said. He said that Pyongyang’s actions were "inhumane," warning that the move amounts to driving inter-Korean relations back into a "state of confrontation.”

"The North's postponement shattered the thrill and hopes of nearly 200 families overnight and deserves denunciation as an inhumane act."

Kim also questioned North Korea’s intentions in mentioning “patriotic individuals” and said that South Korean government and its people will act sternly to protect democracy.

In its statement, Pyongyang warned Seoul that it will not standby while “patriotic individuals” are subjected to oppression in denouncing the South Korean government’s investigation into Unified Progressive Party’s Rep. Lee Seok-ki. Lee and a number of individuals connected to the minor opposition party are currently under investigation for planning a revolt.

South Korea’s two main political parties also berated Pyongyang for the decision.

"The act of breaching an agreement ... as if turning the palm upside down demonstrates that North Korea still does not understand the principles of diplomacy," Rep. Yoo Il-ho, spokesman of the ruling Saenuri Party, said.

Rep. Bae Jae-jeung of the main opposition Democratic Party said the North should understand that such an about-face in its position never contributes to improvement in inter-Korean relations. She also urged the South's government to make greater efforts to get Pyongyang back to the negotiating table.

  

By Choi He-suk and news reports