North Korean leader Kim Jong Un's sister and close aide said Tuesday that U.S. expectations for bilateral talks could bring "disappointment," state-run media reported.

Kim Yo Jong's remarks came after White House National Security Adviser Jake Sullivan on Sunday described as an "interesting signal" comments by Kim Jong Un that he is ready for "dialogue and confrontation" with the United States.

"A Korean proverb says that 'In a dream, what counts most is to read it, not to have it.' It seems that the U.S. may interpret the situation in such a way as to seek a comfort for itself," Kim Yo Jong said in a statement carried by the Korean Central News Agency.

"The expectation, which they chose to harbor the wrong way, would plunge them into a greater disappointment," she added.

At a plenary meeting of the Central Committee of the ruling Workers' Party of Korea held on Thursday, Kim Jong Un pledged to prepare for both "dialogue and confrontation" with the administration of U.S. President Joe Biden.

It is thought to be the first time Kim Jong Un has publicly expressed eagerness to talk with the Biden administration since it came to power in January, with denuclearization negotiations between North Korea and the United States stalled for around 18 months.

North Korea is believed to have been reluctant to hold bilateral talks with the Biden administration unless Washington withdraws what Pyongyang considers its hostile policy position.

Some foreign affairs experts, however, said Kim Jong Un might be keen to resume communication to receive U.S. economic aid, with the North Korean economy languishing amid the novel coronavirus pandemic.

On Monday, meanwhile, U.S., Japanese and South Korean envoys agreed that the three nations will continue cooperating toward the complete denuclearization of the Korean Peninsula through an early resumption of dialogue with the North.

At the outset of their in-person meeting in Seoul, Sung Kim, the newly appointed U.S. special representative for North Korea, voiced hope for a positive response from Pyongyang in the wake of U.S. overtures for dialogue.

At their first summit in 2018 in Singapore, Kim Jong Un and Biden's predecessor Donald Trump agreed that Washington would provide security guarantees to Pyongyang in return for "complete" denuclearization of the Korean Peninsula.

The following year, they fell short of bridging the gap between U.S. demands and North Korea's calls for sanctions relief at their second summit in the Vietnamese capital Hanoi.

Trump and Kim Jong Un met in June 2019 at the Demilitarized Zone dividing the two Koreas, but bilateral negotiations have been at a standstill, with a working-level meeting held in the Swedish capital Stockholm in October that year ending without progress being made.

The Biden administration plans to keep its North Korea policy flexible, while building on the 2018 summit agreement that included Pyongyang's commitment toward denuclearization.

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