SKorea's Park warns of instability if North tests nuke

South Korean president insisted Thursday that another North Korean nuclear test would "shake the security order of Northeast Asia".

Park Geun-hye's warning during a Cabinet meeting came as Seoul has repeatedly cited satellite imagery suggesting that Pyongyang has already completed preparations for a fifth ever nuclear test.

The South is particularly cautious because its northern neighbor is considered more likely to carry out a major provocation as a political statement ahead of its first party congress in nearly 40 years.

North Korea announced this week that the gathering would kick off May 6.

"Ahead of its seventh party congress, Pyongyang has been preparing for an additional nuclear test and it is now in a situation where it can conduct a test anytime it decides to do so," Park was quoted as telling government officials by local news agency Yonhap.

North Korea has shown no sign of heeding global warnings after being struck with toughened sanctions last month in response to January's fourth nuclear test.

In addition to continued ballistic missile exercises, the North has set up a replica of Seoul's presidential office for an imminent artillery drill according to South Korean military officials Wednesday.

Pyongyang views itself as a victim of United States-led aggression -- a North Korean foreign ministry spokesperson told the state-run KCNA news agency Thursday that Washington sees sanctions "as a major means for pursuing its foreign policy."

Another constant grievance held by the North is the alliance between the U.S. and South Korea, where nearly 30,000 American military personnel are based as a legacy of the unresolved 1950-53 Korean War.

But Pyongyang's usual ally China has also vowed to implement United Nations sanctions against North Korea, leaving the reclusive state in danger of further isolation.