North Korea has rejected any further talks with South Korea, calling its decision "completely the fault of South Korea's actions".
It issued a statement in response to a speech by South Korea President Moon Jae-in on Thursday.
Meanwhile, early on Friday North Korea test-fired two missiles into the sea off its eastern coast, the South Korean military said.
It is the sixth such test in less than a month.
The two "unidentified projectiles" were fired about 08:00 (23:00 GMT Thursday) and travelled 230km (140 miles) reaching an altitude of 30km (18 miles), South Korea's Joint Chiefs of Staff said.
Six days ago, North Korea fired two short-range ballistic missiles into the Sea of Japan.
The series of tests comes after US President Donald Trump and North Korean leader Kim Jong-un agreed during a meeting in June to restart denuclearisation negotiations.
North Korea has faced international sanctions for its development of nuclear weapons.
(Sources: BBC News)