The "Tailored Deterrence Strategy against North Korea Nuclear and other WMD Threats" was signed by South Korean Defense Minister Kim Kwan-jin and visiting U.S. Defense Secretary Chuck Hale during their annual security consultative meeting.
A joint statement said the new strategy establishes a strategic alliance framework for tailoring deterrence against key North Korean nuclear threat scenarios, South Korea's Yonhap News reported.
Hagel stressed the commitment of the United States to support deterrence capabilities with its full range of military capabilities, including its nuclear umbrella, conventional strikes and missile defense, the report said.
A senior South Korean Defense Ministry official said the new plan details contingency counter-actions against various nuclear provocations, calling for pre-emptive strikes against the origin of attack if the North were to use its nuclear weapons.
The United States currently has 28,500 troops stationed in South Korea and uses its nuclear warhead capacity as a counterweight to any North Korean threat.
The North Korean threat has increased since the Communist country under its new leader, Kim Jon Un, conducted its third nuclear test in February. South Korean experts say the North has made considerable progress in developing a fairly robust nuclear program in the past three years and is capable of making atomic weapons at any time, Yonhap said.
This year marks the 60th anniversary of the Korean War armistice and the U.S.-South Korea alliance.
On Tuesday, Army Gen. Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff, who was also visiting South Korea, told reporters traveling with him that the alliance is strong, but the two sides cannot become complacent in face of changes in North Korea, the Defense Department reported on its website.
The general said the United States is concerned about the North Korean nuclear capability. He said while the North Koreans have not demonstrated they can weaponize a nuclear weapon, "we can't be complacent about the possibility."
The general said South Korea is America's oldest ally in the region and it would be in the United States' interests to maintain the partnership and continue enhancing it.
Couple calls 9-1-1 over missing hash browns; assault McDonanld's employees
Wisconsin business offering 'therapeutic cuddling' forced to close