South Korea should consider breaking away from a treaty on the non-proliferation of nuclear weapons, a former ruling party leader said Sunday, arguing the country fell into a "state of national emergency" following North Korea's latest nuclear and missile tests.

"It is an empty cry at the weak and self-deception for South Korea to stick to the Joint Declaration on Non-nuclear Korean Peninsula only to maintain our morally dominant position at a time when the gap between the two Koreas' asymmetric warfare capabilities is widening with the North's possession of nuclear weapons," Chung Mong-joon, a former leader of the governing Saenuri Party, said in a post on his blog.

"I'm not saying that we should quit the treaty right now but should explain to the world what's wrong with the NPT system that failed to bar Pyongyang from pursuing nuclear programs and work out measures to exercise our rights."

South Korea is a member country of the Non-Proliferation Treaty which bans non-nuclear states from newly possessing nuke devices. The North walked out of the treaty in 1993.

In the non-nuclear agreement signed in 1991, the two Koreas pledged not to test, produce, receive, possess, store, deploy or use nuclear weapons and not to possess facilities for nuclear reprocessing and uranium enrichment.

The United States accordingly pulled all surface- and sea-launched short-range tactical nuclear weapons out of its army bases in South Korea and then South Korean President Roh Tae-woo also announced principles for ensuring the peace and non-nuclear status of the peninsula. (Yonhap)