SEOUL, South Korea (AP) -- North Korea accused the United States Sunday of preparing to attack it and said it would review parts of the armistice that ended the Korean War five decades ago.

North Korea cited U.S. military plans to relinquish control of a key outpost along the tense border between the two Koreas.

The turnover of Observation Post Ouellette would mean U.S. troops would no longer be responsible for patrolling the heavily fortified buffer area, called the Demilitarized Zone.

Those duties would fall to South Korea, which has a 600,000-member military staring off against North Korean forces. The North's army is the world's fifth largest with 1.1 million soldiers.

"The U.S. decision to take even its small force out of ... Panmunjom ... indicates that the U.S. preparations for a pre-emptive attack upon the DPRK are underway at a final phase," said a spokesman for the North Korean army's mission in the truce village of Panmunjom, according to KCNA, the North's official news agency.

DPRK stands for Democratic People's Republic of Korea, or North Korea.

The North's army "will comprehensively examine" sections in the armistice that deal with security and communications in Panmunjom, the spokesman said.

He said the North would "go into prompt action when necessary to take measures for protecting the security and interests in this area." He did not elaborate.

The United States is reviewing its military posture in South Korea as part of a global realignment to make its forces more nimble and technology-driven. The turnover is planned this year but no date has been set.

The United States has about 37,000 troops stationed in South Korea, but has long kept fewer than 200 soldiers along the DMZ, at Observation Post Ouellette and Panmunjom.

The troops are regarded as a "tripwire" because they would presumably incur casualties during a North Korean attack, thereby prompting U.S. intervention.