North Korea accused the United States on Sunday of stepping up preparations to attack and said that justified the communist state's nuclear weapons program.

North Korea's Minju Joson newspaper cited planned drills with South Korea and other U.S. military activity in the Asia-Pacific region as evidence Washington was preparing to invade.

A day earlier, the North put off Cabinet-level talks with the South to protest the joint military exercises.

The weeklong exercises later this month will involve 20,000 American troops and an undisclosed number of South Korean soldiers. The United States and South Korea characterize them as purely defensive.

"The U.S. strengthening military moves on and around the Korean Peninsula is nothing but a premeditated maneuver to realize its hostile policy aimed at militarily stifling our republic," the North Korean newspaper said in a commentary carried by the official Korean Central News Agency.

"Under the current tense situation, the nuclear deterrent force of our republic effectively contributes to guaranteeing peace and safety of our republic ... (We) will make every effort to solidify our self-defense force."

North Korea claims it has atomic weapons and usually refers to its nuclear arsenal as a "nuclear deterrent force." That claim has not been verified independently.

Meanwhile, a South Korean official said Sunday that North Korea may join an international anti-money laundering organization to prove its commitment to fighting financial crimes after being accused of counterfeiting and other misdeeds by the United States.

North Korean officials expressed their intention to join an unspecified group at a meeting in New York last week on U.S. financial restrictions imposed on Pyongyang for alleged counterfeiting and money laundering, the official said on condition of anonymity, citing the sensitive nature of the subject.

North Korea has said it will not return to six-nation talks on its nuclear program unless Washington lifts restrictions placed on a Macau bank and several North Korean companies.

The United States has urged the North to come back to the negotiating table without conditions. The talks include both Koreas, the United States, China, Japan and Russia.

The communist state has long claimed the United States is bent on invading the country, condemning annual joint military exercises with South Korean troops as a "rehearsal" for an attack.

The two Koreas had planned to discuss exchange projects in a meeting this month that is part of the highest-level regular dialogue between the two sides.

The two sides are still technically in a state of conflict because the 1950-53 Korean War ended in a truce, not a peace treaty. Relations warmed significantly after an inter-Korean summit in 2000.