Gates said the support would include U.S. conventional and missile capabilities as well as the "U.S. nuclear umbrellas" as a deterrent to the North.
"North Korea's emerging nuclear weapons programs have a destabilizing effect both regionally and internationally," Gates told a joint news conference in Seoul with South Korean Defense Minister Kim Tae-young.
South Korea's Yonhap news agency said Gates and Kim met for three hours Thursday to discuss security issues, including the ongoing economic issues in North Korea and the anticipated succession of power from the ailing Kim Jong-il.
Gates' statement was in line with earlier remarks from Secretary of State Hillary Clinton, who said recently in Washington that sanctions against North Korea would not be relaxed until Pyongyang took concrete steps to wind down its fledgling nuclear program.
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