The Democratic People's Republic of Korea (DPRK) Saturday warned against the two upcoming U.S.-South Korean joint military exercises, comparing the maneuvers to a declaration of war.

In an article published by the official news agency KCNA, the DPRK's National Defense Commission called the planned military exercises "a blatant challenge to peace and security on the Korean Peninsula."

The United States and South Korea are planning two joint military exercises, "Key Resolve" and "Foal Eagle," starting next week till the end of April.

The National Defense Commission warned in the article that the military exercises are in essence "a silent declaration of a war," which will be accompanied by a "corresponding physical retaliation."

Earlier in the week, South Korea conducted live-fire drills despite the DPRK's threat of retaliation.

The two-hour drills on Monday were held in waters off South Korea's western border islands of Yeonpyeong and Baengnyeong, located near a tense Yellow Sea border the DPRK refuses to acknowledge.

The volatile maritime border, called the Northern Limit Line, was drawn by the U.S.-led United Nations Command at the end of the 1950-53 Korean War that ended with a truce.

A fierce artillery fire exchange occurred between the two sides near Yonphyong Island in November 2010, killing four South Koreans. Both sides accused the other of firing the first shot.