North Korea has threatened not to resume talks with South Korea unless issues leading to the suspension of a high-level meeting this week are resolved.
Chairman of North Korea's Committee for the Peaceful Reunification Ri Son Gwon made the statement on Thursday.
He also slammed the recent joint military drill between South Korea and the US.
North Korea says it is angry about a large military exercise called Max Thunder that's currently being staged by Washington and Seoul in South Korea.
According to North Korea's official news agency, KCNA, Ri criticized the South for participating in the drills, as well as for allowing "human scum" to speak at its National Assembly.
"Unless the serious situation, which led to the suspension of the north-south high-level talks, is settled, it will never be easy to sit face to face again with the present regime of south Korea," the statement said without further elaboration.
North Korea has called the drills an "undisguised challenge" and a "deliberate military provocation" against the apparent strides toward peace.
Baek Tae-hyun, a spokesman for South Korea's Unification Ministry, confirmed that North Korea had canceled Wednesday's talks with the South.
Baek said at a briefing for reporters that Seoul "is urging North Korea to come to the talks soon for the sake of peace and prosperity on the Korean Peninsula."
The new development came after Pyongyang threatened to cancel an unprecedented summit between its leader Kim Jung-un and US President Donald Trump.
Washington will "have to undertake careful deliberations about the fate of the planned North Korea-US summit in light of this provocative military" said the North's official news agency KCNA on Tuesday.
"This exercise, targeting us, which is being carried out across South Korea, is a flagrant challenge to the Panmunjom Declaration and an intentional military provocation running counter to the positive political development on the Korean Peninsula," it added.
Shortly after the announcement, Washington said that it was continuing with preparations for meeting between Trump and Kim.
The summit had been scheduled between Kim and US President Donald Trump in Singapore on June 12.
North Korean leader Kim Jong-un met with South Korean President Moon Jae-in in a historic summit last month. They issued the declaration at the end of the summit. Moon has also said Kim has promised to give up its nuclear program.
The two sides have been reaching out to one another since January. Until then, inter-Korea relations were marked by hostility and permanent fears of war.