North Korea could conduct another nuclear test as early as this month given Pyongyang's methods since the early 1960s, a Korean professor at America's Tufts University predicts.

Foreign Affairs magazine published an article entitled "The Pyongyang Playbook" in which Prof. Lee Sung-yoon writes that the North's strategy has been to "lash out at its enemies" when they seem weak or distracted, fueling international condemnation, and then negotiate for concessions in return for peace.

Based on this formula Lee speculates that the North will likely conduct another nuclear test possibly next Wednesday, the eve of North Korea's anniversary, or on Oct. 10, the anniversary of the Workers Party and could then attempt to start afresh with peace talks early next year.