ASAN MAINA, Guam—The US Marine Corps on Thursday formally opened its new base on the U.S. territory of Guam that will host about 4,000 troops currently stationed in Japan's Okinawa, with the personnel transfer slated to begin in 2024.

US and Japanese officials attended a ceremony on the Pacific island marking the formal launch of Camp Blaz, whose $8 billion construction project has been funded with close to $3 billion from the Japanese government.

The officials stressed steady progress in the construction of the base at the event, held on Guam's historic Asan Beach, where US Marines landed in July 1944 to reclaim the island after more than two years of Japanese occupation.

"The relocation of U.S. Marine Corps units from Okinawa to Guam beginning in 2024 will be crucial to enhancing the deterrence of the alliance in the region and to mitigating impact on Okinawa," said Jiro Kimura, Japan's parliamentary vice minister of defense.

The Marines' Guam transfer is based on a 2006 force realignment plan between the United States and Japan that partly seeks to reduce Okinawa's base-hosting burdens. The remote island hosts the bulk of U.S. forces in Japan and its residents have for decades bristled at crimes and pollution linked to the military presence.

At Thursday's ceremony, a small group of protesters showed up with anti-US base banners.

Activist Monaeka Flores told Kyodo News that the military buildup would only make Guam "a target for a war that we didn't want to be part of."

But Guam Gov. Lou Leon Guerrero, who has supported the Marines' relocation, said at the ceremony that officials conducted a "comprehensive review" of the construction project to determine its benefit for the residents and for national and regional security.

"The future of Guam is inseparable from the future of the broader Indo-Pacific. And the success of the Marines is inseparable from the success of Guam's people," she said.

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Camp Blaz is named after the late Marine Brig. Gen. Vicente "Ben" Blaz, a Guam native who also served as the territory's representative in the US House of Representatives.

Even though the Marines partially activated the base in October 2020, its construction is still ongoing, including the main cantonment, barracks and galley.

Among the other participants from Japan at Thursday's ceremony were members of the Self-Defense Forces as well as parliamentary vice foreign minister Yuumi Yoshikawa.