South Korea has condemned North Korea for its latest threats of a fourth nuclear test, saying the regime will face severe consequences for its actions.
In a statement, Seoul's foreign ministry warned North Korea to keep in mind that it will pay the price if it neglects the grave demands from its neighbors and the international community and pushes ahead with another nuclear test.
The United States also urged North Korea to refrain from disturbing regional peace and security.
An official at the U.S. State Department said any nuclear tests or ballistic missile launches are a grave violation of UN Security Council resolutions and said such actions will only further isolate Pyongyang.
North Korea raised tensions Sunday by threatening to conduct a new type of nuclear test.
"We would not rule out a new form of nuclear test for bolstering our nuclear deterrence."
The threats came in response to a UN condemnation of North Korea's medium-range Rodong ballistic missile launches last week.
It was the first firing in four years of mid-range missiles, following a series of short-range rocket launches over the past two months.
According to 38 North, a website run by the U.S.-Korea Institute at Johns Hopkins University, recent satellite imagery shows mountains north and south of North Korea's Punggye-ri test site have been excavated into complexes that could allow multiple tests.
Joel Wit, a former state department official and editor of the 38 North website, said there are no immediate signs of a fourth nuclear test but added North Korea will be capable of carrying out a test within four to six weeks, once it decides to do so.
Hwang Sung-hee, Arirang News.
Seoul's Unification Ministry also said in a press briefing Monday morning that while North Korea is capable of conducting a nuclear test and firing long-range missiles, it sees no imminent signs of a fourth nuclear test or a missile launch.