Officials from both countries released a statement Friday at the end of the 40th Security Consultative Meeting in Washington, The Korea Times reported.
The agreement calls for U.S. military forces stationed in South Korea to be reinforced by 690,000 personnel, 2,000 planes and 160 military vessels in the event of war.
U.S. troops have been based in South Korea since the truce that ended the Korean War more than 50 years ago.
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