US warns 'overwhelming' response to any NKorea use of nukes

WASHINGTON -- The United States warned Wednesday that any attack on American allies or use of nuclear weapons by North Korea would be met with an "overwhelming" US response as it sought to reassure close ally South Korea that the US has its back.

The statement by Defense Secretary Ash Carter came as top US and South Korean diplomats and military officials met, weeks after North Korea's most powerful nuclear test explosion to date, and days after its failed test launch of a ballistic missile -- one of more than 20 such tests this year alone.

"Make no mistake, any attack on America or our allies will not only be defeated, but any use of nuclear weapons will be met with an overwhelming and effective response."