North Korea's official news agency, KCNA, claimed on Sunday that South Korean President Yoon Suk-yeol's travel to the US was a provocation and a typical demonstration of hostile policies against Pyongyang, and that it effectively makes a nuclear war against North Korea "a fait accompli." 

The presidents of South Korea and the United States signed the Washington Declaration on Wednesday, which calls for the establishment of a regular bilateral dialogue mechanism on extended deterrence and strategic planning. South Korea also obtained a US vow to deploy "the entire force of the alliance," including nuclear weapons, as soon as North Korea launches a nuclear assault.

In the event of Pyongyang's aggressiveness, Washington has informed Seoul that it will employ all available means, including nuclear weapons, and has pledged to send nuclear missile submarines to the Korean Peninsula.

"This trip, aimed to draw up a sinister plan between the master and the stooge to annihilate the DPRK [North Korea], is the most hostile, aggressive and provocative, dangerous trip for a nuclear war... The 'Washington Declaration' on raising the practicality of the 'extended deterrence' provided by the U.S. is a typical product of the heinous hostile policy towards the DPRK," KCNA stated. 

KCNA called Yoon a "Traitor," adding that the visit made it possible to "reconfirm the hostile intention of the US and the puppets which can never be changed but has become more reckless. This shows that the DPRK should neither hesitate nor stop for even a little and even a moment to become more stronger and more thoroughly prepared... The dangerous nuclear war moves of the US and the puppet group running amuck in stifling the DPRK while denying its existence can never be pardoned, and they will have to pay dearly for their rash acts," 

Kim Yo Jong, the sister of DPRK leader Kim Jong Un, had issued a warning about the "more serious danger" that would result from a US-South Korea agreement aimed at strengthing deterrence against Pyongyang, state media reported.

Her remarks came after US President Joe Biden and his South Korean counterpart threatened to end DPRK's leadership if it uses its nuclear arsenal, issuing the Washington Declaration in which the US will pledge to bolster its commitment to a so-called "extended deterrence" to counter the threats posed by the DPRK and mobilize a wide range of its military capabilities.