Japan and the United States on Friday confirmed their cooperation on North Korea as the reclusive state rebuffs calls to resume denuclearization negotiations, while Washington conveyed its continued readiness for dialogue with Pyongyang.

In a meeting in Tokyo, Foreign Minister Toshimitsu Motegi stressed to visiting U.S. Deputy Secretary of State Stephen Biegun the need to strengthen the Japan-U.S. alliance in an ever-changing security environment.

U.S. Deputy Secretary of State Stephen Biegun (L) and Japanese Foreign Minister Toshimitsu Motegi meet in Tokyo on July 10, 2020. (Pool photo) (Kyodo)

"It is crucial that Japan and the United States work together to maintain and bolster a free and open Indo-Pacific region," Motegi said.

Biegun, who was on a two-day visit to Tokyo after making a stop in Seoul to speak with South Korean officials, replied, "As we face new challenges in this era, it is ever more important for us to work closely together."

In separate meetings with Motegi and Defense Minister Taro Kono among other Japanese officials, Biegun "emphasized continued U.S. readiness to engage in dialogue with the DPRK," the State Department said, referring to the acronym for Democratic People's Republic of Korea, North Korea's official name.

Biegun also discussed with the Japanese officials "the importance of continued close cooperation with Japan and other like-minded partners on promoting a free and open Indo-Pacific and countering efforts by those who seek to undermine good governance and the rules-based international order," in an apparent reference to China, which has been flexing its muscles in territorial disputes in the South and East China seas.

Japanese Defense Minister Taro Kono and U.S. Deputy Secretary of State Stephen Biegun pose ahead of their talks in Tokyo on July 10, 2020. (Pool photo) (Kyodo)

The U.S. special representative for North Korea also met separately with Shigeru Kitamura, national security adviser to Prime Minister Shinzo Abe.

Relations between the two Koreas have sunk to their lowest level in years following the North's demolition of an inter-Korean liaison office on its side of the border in mid-June.

Senior North Korean officials have also lashed out at the United States in recent days, rejecting the possibility of resuming negotiations that have been deadlocked since a summit between U.S. President Donald Trump and the North's leader Kim Jong Un collapsed in early 2019 over disagreements on sanctions relief.

Kim's sister and close aide, Kim Yo Jong, issued a statement Friday saying Pyongyang is not willing to arrange another summit this year unless Washington changes its stance.

The United States and its allies in Asia are facing security challenges including China's growing assertiveness, seen both in its actions in surrounding waters and the enactment of a new national security law in Hong Kong, a move that has drawn criticism for undermining the "one country, two systems" principle.

U.S. Deputy Secretary of State Stephen Biegun speaks during a meeting with Japanese Foreign Minister Toshimitsu Motegi in Tokyo on July 10, 2020. (Pool photo) (Kyodo) 

"In the time of coronavirus and COVID-19, we still have to worry about some country trying to change the status quo with force," Kono said in his meeting with Biegun.

Biegun is the highest-ranking U.S. official to visit Japan since travel restrictions were imposed to curb the spread of the novel coronavirus.

He and his staff were exempted from the entry ban on people traveling from the United States and South Korea on condition that they be tested for COVID-19, the respiratory disease caused by the virus, and avoid contact with members of the public.