North Korea issued new threats against the South and its allies on Tuesday, saying it views a recent expansion of United Nations Security Council sanctions as an act of war.
In a commentary filled with typically inflammatory language, the official Korean Central News Agency promised "merciless retaliatory blows" and a "grand and just war for national reunification" in response to the sanctions.
The commentary did not mention the nuclear test threatened by North Korea last week following the unanimous Security Council decision, which punished Pyongyang for a December rocket launch.
South Korea's foreign ministry on Tuesday again denounced the nuclear test threat. It urged its communist neighbor to "pay heed to the continued warnings from the international community and not push ahead with any further provocations."
Seoul on Tuesday announced the creation of a special task force to monitor North Korea's nuclear test site. Recent satellite photos suggest increased activity at the site. South Korean officials have said they believe a test could be carried out at any time.
North Korea also conducted nuclear tests in 2006 and 2009 following U.N. condemnations of earlier long-range rocket launches. It is barred from conducting nuclear or ballistic missile tests under international sanctions.