North Korea on Thursday threatened to turn South Korea and the United States into a "sea of fire" as it continued to slam the allies for preparing for joint military drills.

Rodong Sinmun, North Korea's main newspaper, berated the U.S. for preparing for the Key Resolve command post exercise, denouncing it as maneuvers aimed at "decapitating" the North Korean leadership.

Seoul and Washington plan to conduct their largest-ever military drills starting early March, involving a series of strategic weapons. The North has claimed the drills are a rehearsal for a northward invasion.

"The situation came to a point where (the joint drills) dare to target our revolutionary leadership," the newspaper said, noting the drills would be tantamount to a "declaration of war."

"Let's turn Seoul and Washington into a sea of fire," it said.

North Korea also threatened to "turn U.S. military installations in the Asia-Pacific region and the U.S. mainland into ashes" should the U.S. fail to come to its senses.

The planned exercise comes on the heels of Pyongyang's recent nuclear and long-range missile tests, drawing international condemnation.

The North's menacing rhetoric came two days after the North's military warned of a "pre-emptive" strike against South Korea and the U.S. over any attempt to collapse the North's regime.

The Supreme Command of the North's military threatened to pre-emptively strike Cheong Wa Dae and U.S. bases in the Asia-Pacific as it criticized the allies' plan to stage the military exercises.

The newspaper also carried photos related to the 1950-53 Korean War and the North's seizure in 1968 of the U.S. intelligence ship "Pueblo," claiming that the North's past conflicts with the U.S. ended with "the U.S. surrender and apology." (Yonhap)