Amid criticism from North Korea, the U.S. and South Korea ready their militaries.
The preparations are part of an annual joint drill called Key Resolve and Foal Eagle 2012.
American officers said the deployment exercise at a base south of Seoul is designed to help counter potential threats.
(SOUNDBITE)(English) U.S. LIEUTENANT COLONEL DOUGLAS PIETROWSKI, COMMANDER OF ARMY FIELD SUPPORT BATTALION OF NORTHEAST ASIA, SAYING:
"Foal Eagle enhances the ROK (Republic of Korea: South Korea) and U.S. alliance's ability to defend the Republic of Korea, to protect the region and maintain sustainability of the Korean peninsula."
The exercise began last week and is scheduled to run through April.
North Korea has criticised the drills, broadcasting footage of its own military preparations.
SOUNDBITE) (Korean) DEPUTY COMMANDER LI GUM-CHOL SAYING:
"We will turn Seoul into a sea of flames by our strong and cruel artillery firepower, which cannot be compared to our artillery shelling on Yeonpyeong Island. We are training hard, concentrating on revenge to shock Lee Myung-bak's traitorous group and the military warmongers in South Korea."
The North's threats may be an attempt to gain an advantage in nuclear disarmament negotiations with the U.S. and consolidate power under new leader, Kim Jong-un, who replaced his father after his death in December.
Lindsey Parietti, Reuters
