North Korean leader Kim Jong Un supervised a ballistic rocket launching drill of Hwasong artillery units of the Strategic Force of the KPA on the spot in this undated photo released by North Korea's Korean Central News Agency, in Pyongyang, March 7, 2017. REUTERS

The United States wants to go to war in and around North Korea and South Korea, a political party based in the North Korean capital of Pyongyang warned on Friday. The Central Committee of the Korean Social Democratic Party sent a letter to politicians in the South appealing to them to unite against "the chieftain of aggression": The U.S.

"All the parties and people from all walks of life in South Korea should rise up in the anti-U.S., anti-war struggle for peace, clearly seeing through the nature of the U.S., the chieftain of aggression and disturber of peace," the letter said in part. "All Koreans should turn out in the struggle to resolutely check the reckless nuclear war drills of the U.S. and South Korean warmongers."

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The letter came after weeks of contentious exchanges of rhetoric and aggressive posturing between the three nations. Hours after North Korea's actions on Friday, the U.S. moved to impose sanctions a group of North Koreans and a company based there because of their ties to Pyongyang's nuclear and banking programs.

"Today's sanctions are aimed at disrupting the networks and methods that the Government of North Korea employs to fund its unlawful nuclear, ballistic missile, and proliferation programs," Treasury Secretary Steven Mnuchin said in a brief statement released Friday. "I urge our partners and allies to take similar measures to cut off its funding."

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Actions by the U.S. compelled North Korea to build up its nuclear program in the first place, a North Korean official insisted Thursday. Dating back to America's use of nuclear weapons in World War II, the U.S. has been using them "to threaten and blackmail other countries," North Korean diplomat Ri Song Chol told the Associated Press.

South Korean defense officials on Wednesday directed its armed forces to react to North Korean provocations with "on-the-spot" and "decisive" military action. That directive came days after U.S. Secretary of State Rex Tillerson said "all options are on the table" in responding to North Korea, suggesting military action could be resorted to if Pyongyang continues its recent series of ballistic missile launches.