The powerful sister of North Korean leader Kim Jong Un called the U.S. push for denuclearization of her country an “anachronistic dream,” a day before Chinese President Xi Jinping’s visit to North Korea, which is the first in seven years. 

“The U.S. assertion to backbite the status of the DPRK as a nuclear weapons state has no legally binding force and no one will be bound by the U.S. unilateral rhetoric,” said Kim’s sister and senior official Kim Yo Jong in a statement distributed by the Korean Central News Agency (KCNA).

She said that the U.S. announcement of President Donald Trump and Xi’s commitment to denuclearization in North Korea, at the Beijing Summit last month, was false. 

“Some officials in the United States have failed to wake from their escapist and anachronistic dream,” she said. 

Kim Yo Jong also accused the U.S. and South Korea of pushing for “ceaseless arms build ups” in her statement, and said that “steadily beefing up the nuclear war deterrent for self-defense” was “an irreversible final conclusion to be carried out unconditionally.”

North Korea has focused on expanding its nuclear arsenal since diplomacy with Donald Trump collapsed in 2019, when Trump demanded complete denuclearization in exchange for U.N. economic sanctions relief.

Last week, Kim Jong Un announced plans to grow the country’s nuclear forces “at an exponential rate”, and revealed a new facility to produce nuclear bomb fuels. 

After a visit to the new site on June 3, Kim and his top officials “confirmed the order of priority for implementing the ambitious future plan designed to beef up our state’s nuclear forces at an exponential rate,” according to the KCNA. 

KCNA said the facility used “more sophisticated technology” but did not disclose other details. 

South Korea’s Joint Chiefs of Staff said the site was likely a uranium enrichment plant, and that it was closely coordinating with the US to monitor nuclear activities in North Korea. 

This is the third time North Korea disclosed a uranium enrichment site, showing one at its main Yongbyon nuclear complex to visiting American scholars in 2010, and releasing photos of another uranium enrichment plant believed to be at its Kangson complex in 2024.

On Sunday, North Korea’s state media also reported that Kim Jong Un visited a weapons factory the day before, calling for a 2.5 times increase in the nation’s missile production capacity under a five-year plan period. 

Experts say that Kim wants recognition as a nuclear state to demand the lifting of U.N. economic sanctions, according to the Associated Press. They also note that North Korea has not proved it has mastered the last remaining technological hurdles for nuclear missiles capable of striking the U.S. mainland. 

Analysts said that during the Xi-Kim summit, Xi would likely refrain from raising the denuclearization issue but offer economic assistance programs, reasserting China's influence over North Korea which has shifted to Russia recently, the wire service also reported.

North Korea has sent 11,000 to 15,000 troops to Russia to support its war efforts against Ukraine, according to the U.S. Pentagon and Ukrainian intelligence estimates. South Korean and U.S. officials have said North Korea obtained economic and other assistance from Russia in return. 

Xi called for deeper “strategic coordination and cooperation” with North Korea after receiving a lavish red-carpet welcome. Xi also told Kim “no matter how the international situation changes, the firm position of the Chinese Party and government highly valuing the traditional friendship between China and North Korea will not change,” according to a readout by Chinese state-controlled media Xinhua.