Japan's Prime Minister Kishida Fumio and a US military commander say their countries will work closely so their alliance will make them better able to deter and tackle threats.
This comes as China is stepping up its military activities in the region.
Kishida met Thursday with the Commander of the US Indo-Pacific Command, Admiral John Aquilino.
Kishida said, "By further promoting cooperation between Japan and the United States, we want to realize a free and open Indo-Pacific and work together for the stability of the region and the international community."
Admiral Aquilino said he'll work with the top officer of Japan's Self-Defense Forces, Yamazaki Koji.
He said, "My commitment to you is that I will work with General Yamazaki to deliver a free and open Indo-Pacific, and peace and stability, and prosperity for the region."
Japanese officials say Kishida and Aquilino shared serious concern over China's unilateral attempts to change the status quo.
They also discussed North Korea's nuclear and missile development.
They agreed it's important to steadily reorganize the US military in Japan so as to maintain deterrence and ease the burden on communities that host US facilities.
Kishida urged the US to run its bases safely.
Japan's Defense Ministry says Aquilino and SDF Chief of Staff Yamazaki inspected defense activities in southwestern Japan this week.
They visited SDF camps on the remote islands of Yonaguni and Amami-Oshima.
Ministry officials say Aquilino and Yamazaki observed the region by helicopter and shared information about the situation and SDF activities there.
The ministry is deploying new units to strengthen defense in the region.