President Park Geun-hye warned Monday North Korea will "pay" if the communist nation launches attacks like its sinking of a warship and shelling of a border island in 2010.
Park made the remark during an interview with CBS television broadcast Monday.
"Yes, we will make them pay," Park said in response to whether South Korea will respond militarily if North Korea launches small-scale attacks like the ones in 2010 that claimed the lives of 50 South Koreans.
Park also called for an end to rewarding North Korea's bad behavior.
"North Korea engages in provocations, threats. This is followed by negotiations and assistance. And so, we saw an endless continuation of this vicious cycle, and it's time for us to put an end to that cycle," she said.
Park also said she has a message to North Korean leader Kim Jong-un.
"I would tell him that North Korea must change. That is the only way for survival and the only way for development," she said.
Park also said the North has such a weak rationale that it is resorting to personal attacks on her, such as the accusation that the "venomous swish" of her skirt is making South Korean officials engage in "warmongering."
"In my view, the various facts that they are not basing their comments on facts but resorting to various ad hominem attacks, referring to my dress ... is a sign that they have a very weak rationale and their rationale is extremely weak, and so they feel very cornered," she said. "I think it's a telling sign of that."
During talks with U.N. Secretary-General Ban Ki-moon earlier in the day, Park stressed that the North must halt provocations and give up its nuclear programs if it does not want deeper isolation.
The North's policy of seeking both nuclear arms and economic development won't work, she said.
"North Korea is trying to take the course of developing its economy while possessing nuclear weapons in a parallel way. But in fact, (the two) are not compatible, and this is an impossible goal," she said, according to her spokesman Yoon Chang-jung.
South Korea, the United Nations and others are ready to help North Korea's development if the communist nation shows a responsible attitude to the international community, Park added, lamenting that Pyongyang, however, is trying to take the opposite course.
Strong retaliation against provocations is a key part of her North Korea policy, Park said.
"The reason I am pushing for the Korean Peninsula trust process is that we can never tolerate North Korea's nuclear programs. There can never be any reward for North Korean provocations, and we will make them pay if they launch attacks," she said.
"However, if North Korea chooses the right path, we will provide assistance and seek cooperation, and will use our maximum strength to help (North Korea) move forward on the path of co-prosperity," she said.
Despite the tough stance against North Korea's nuclear programs, Park has pledged not to link humanitarian aid for the impoverished neighbor to security issues, a departure from her predecessor Lee Myung-bak, who insisted on liking any assistance to progress in disarming the North.
Park reiterated the stance in the meeting with the U.N. chief.
"There are concerns about infants and other vulnerable brackets in North Korea, and I also believe that we need to provide humanitarian assistance to North Korean residents," she said.
"Under the Korean Peninsula trust process, I intend to provide aid transparently regardless of political situations." (Yonhap News)