North Korea lashed out Thursday at the U.N.’s plans to set up a field office in Seoul to oversee North Korea’s human rights violations, threatening “ruthless retaliation.”

The Rodong Sinmun, the mouthpiece of Pyongyang’s ruling Workers’ Party, denounced Seoul’s support for the U.N.’s scheme and recent resolution over North Korean rights issues as a “vicious disavowal of our dignity and system and an unacceptable provocation.”

The U.N. Office of the High Commissioner for Human Rights plans to open a field structure in Seoul in the coming months to monitor and study the situation across the border. This is in line with a recommendation in February 2014 by the Commission of Inquiry.

“We will never accept the rash acts by the (South Korean) puppet forces, who are devoured by the delusion of a unification (by absorption) and make stern responses,” Rodong Sinmun said.

“Our warning against the U.N. office was never meant to be empty talk,” the paper stated, referring to a statement released Monday by the North’s Committee for the Peaceful Reunification of Korea, which is in charge of cross-border affairs, that it will not “sit idle.”

The North said if the U.N. office was established, it would be the “very first target of our merciless punishment.”

The paper also accused Seoul of consistently conspiring to topple the regime, citing Pyongyang’s recent detainment of two South Koreans which it claims are spies.

“The (South Korean) puppet forces are speaking of trust and dialogue in words, while colluding with the U.S. to frantically press ahead with joint military exercises aimed at invading the North and further intensifying mistrust and confrontation between the North and South through a human rights-themed plot,” the paper said.

“As the puppets are fueling fratricidal confrontation, we have already clearly made sure that the chances are gone for inter-Korean dialogue and improvement for the relationship, and what’s left is confrontation by force.”

By Shin Hyon-hee (heeshin@heraldcorp.com)