South Korea's top military commander said Wednesday that his military is ready to make a "pre-emptive strike" against North Korea, even at the risk of a full-scale war, if there are signs that the North may attack using nuclear weapons ahead of its third nuclear test.

Gen. Jung Seung-jo, the chairman of the Joint Chiefs of Staff, made the remarks during a parliamentary defense meeting convened as tension runs high on the Korean Peninsula after Pyongyang vowed to conduct a nuclear test in retaliation for the U.N. sanction against the country for its December rocket launch. 

Asked if the military is ready to deter North Korea's nuclear attack, Jung said, "If (the North) shows a clear intent to use a nuclear weapon, it is better to get rid of it and go on a war, rather than being attacked."

His remark came after Pyongyang on Tuesday threatened "stronger" measures other than a third nuclear test to cope with "hostile forces' nuclear-war moves," without spelling out the actions it would take.

While the military currently does not have a plan to destroy the North's test site in its northeastern tip, Jung said he will make a decision according to how circumstances develop.

Regarding the type of fissile material, Jung said North Korea is likely to detonate a "boosted fission weapon," a smaller and more sophisticated nuclear bomb, dismissing speculation that the

North is going to test a hydrogen bomb.

A fusion-boosted fission bomb induces nuclear fusion with slight nuclear fission, enabling smaller, lighter bombs with less fissile material for a given yield. Either uranium or plutonium can be used to develop the bomb. (Yonhap News)