The United States regarded the recent comments made by Kim Jong Un, top leader of the Democratic People's Republic of Korea (DPRK), as an "interesting signal," National Security Adviser Jake Sullivan said on Sunday. 

Kim said on Thursday that his country should get prepared for both dialogue and confrontation with the United States, especially for confrontation, to protect the DPRK's dignity and interests for independent development, according to the official Korean Central News Agency. 

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Kim: DPRK must prepare for 'dialogue and confrontation' with U.S.

"His comments this week, we regard as an interesting signal. And we will wait to see whether they are followed up with any kind of more direct communication to us about a potential path forward," Sullivan said in an interview with ABC News. 

He reaffirmed that the Biden administration is prepared to engage in "principled negotiations" with Pyongyang to deal with its nuclear program, with the ultimate objective of the complete denuclearization of the Korean Peninsula. 

Sung Kim, the newly appointed U.S. special envoy for the DPRK, arrived in Seoul on Saturday for a three-way meeting with his counterparts of the Republic of Korea and Japan over the denuclearization issue. 

The Biden administration completed its policy review toward the DPRK at the end of April. The White House said it had reached out to Pyongyang through several channels but had not yet received any response. 

Kim Jong Un and former U.S. President Donald Trump held their first summit in Singapore in June 2018, agreeing on a complete denuclearization of and a lasting peace settlement on the Korean Peninsula. 

But denuclearization talks between Pyongyang and Washington have been stalled since the second Kim-Trump summit ended fruitless in the Vietnamese capital of Hanoi in February 2019. 

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