There is fresh speculation that North Korea intends to detonate another nuclear device this week, Agence France-Presse reported.
"We've heard a North Korean official in Beijing told the Chinese side that the North planned to carry out a nuclear test between Jan. 13-20," an anonymous South Korean government official told the JoongAng Ilbo newspaper. "We're now stepping up surveillance over the Punggye-ri nuclear test site," the source said.
Surveillance satellites in recent months have detected extensive preparations at the North's testing site. Outside experts assess the nation's third underground nuclear blast could occur shortly after the directive from Pyongyang is given.
The North's 2006 and 2009 tests were conducted following rocket tests. Pyongyang most recently launched a long-range space rocket on Dec. 12.
Still, University of North Korean Studies professor Yang Moo-jin said he does not believe the Stalinist state will carry out another nuclear test in the short-term. "Chances are slim that the North might push ahead with a nuclear test in this winter season, especially when China is insisting on a moderated response to the rocket launch to prevent a third nuclear test taking place," he said in an interview.
The North Korean Foreign Ministry in a Monday statement said the country would "continue to strengthen its deterrence against all forms of war," the Associated Press reported. The statement gave no hint as to what specific steps Pyongyang would take to enhance its defense capabilities.