Ministerial talks between North and South Korea have been cancelled after Pyongyang failed to confirm they would take place.
Pyongyang is angry about a UN meeting on the North this week
The meetings, which were due to open on Monday, were to have focussed on inter-Korean exchanges and the North's suspected nuclear programme.
North Korea gave no explanation for its apparent withdrawal. But Pyongyang has criticised Seoul's decision to send non-combatant troops to take part in the war in Iraq, and recent war games with the US, which the North has interpreted as a threat.
The talks would have coincided with a UN Security Council meeting on Wednesday to discuss the North and its controversial nuclear plans.
In a statement released by the official KCNA news agency on Sunday, a North Korean foreign ministry spokesman called the Security Council meeting a provocative act which impeded dialogue and would only aggravate the situation on the Korean peninsula.
Drawing up the hatches
Analysts say that North Korea - described by US President George W Bush as part of an axis of evil, along with Iraq and Iran - may fear it will be the next US military target.
Washington has said it wants to seek a peaceful resolution to the nuclear stand-off.
The North wants bilateral talks with the US to resolve the issue. Washington has insisted any discussions must take place in a multilateral framework.
Last month, North Korea cancelled two sets of working-level
talks with South Korea, after accusing the South of heightening its security alert status.
This week's talks would have been the first, cabinet-level meeting between the two sides since South Korean President Roh Moo-hyun took office in February.
Mr Roh has been pressing for a peaceful resolution to the North Korean nuclear crisis, but his decision to support the war in Iraq has angered both the North, and the majority of the public in his own country.
The South Korean leader has argued that backing the US-led war in Iraq is essential to relations between Seoul and Washington, and hence to security on the Korean peninsula.