The leaders of the United States, Japan, Australia and India on Friday showcased their deepening ties in the face of China's rise, as they expanded areas of cooperation to space and infrastructure, and decided to regularize their "Quad" summit meetings.

During the first in-person summit of the group of major Indo-Pacific democracies, the four leaders also affirmed their progress toward supplying 1 billion doses of coronavirus vaccines across the region as promised in their virtual summit in March.

The first face-to-face meeting among the leaders of Japan, the United States, Australia and India is held at the White House in Washington on Sept. 24, 2021. (Kyodo)

"Together, we recommit to promoting the free, open, rules-based order, rooted in international law and undaunted by coercion, to bolster security and prosperity in the Indo-Pacific and beyond," the four leaders said in their joint statement released after the meeting, adding that their cooperation remains "unflinching."

Although the statement did not directly mention China, the language used in the statement and agenda items discussed were apparently connected to China's assertiveness in the region, including its territorial claims in surrounding waters, as well as trade and other issues.

<HERE is the gist of agreements reached during Quad leaders' meeting>

The four countries also said they will work to "meet challenges to the maritime rules-based order," including in the East and South China seas.

The meeting at the White House, hosted by U.S. President Joe Biden, was attended by Japan's Yoshihide Suga, who is soon stepping down as prime minister, as well as Australian Prime Minister Scott Morrison and Indian Prime Minister Narendra Modi.

"Japan, the United States, Australia, India -- this engagement is completely taking root," Suga told reporters after the gathering, as he announced that the four leaders had agreed to hold a Quad summit every year.

The move may suggest that the Quad, seen as a loose coalition of the four countries, is becoming more of a formalized group under the banner of advancing a "free and open" Indo-Pacific.

The Biden administration has placed emphasis on the Quad as one of the "new configurations" designed to take on the challenges of the 21st century, along with the just-launched Indo-Pacific security partnership between Australia, Britain and the United States, dubbed AUKUS.

(From L) Japan's Prime Minister Yoshihide Suga, India's Prime Minister Narendra Modi,  U.S. President Joe Biden and Australia's Prime Minister Scott Morrison pose for a photo on Sept. 24, 2021, at the White House in Washington. (Photo courtesy of the Japanese Cabinet Public Relations Office)(Kyodo)

Among the agreements reached during the meeting, the Quad countries said they will begin "space cooperation" for the first time, which will include sharing satellite data for peaceful purposes such as monitoring climate change and disaster response.

They also agreed to work to deliver "transparent, high-standards" infrastructure in the Indo-Pacific, possibly as an alternative to Beijing's "Belt and Road" project, bolster supply chain security for semiconductors and advance the deployment of "secure, open, and transparent" 5G telecommunications networks.

The world's semiconductor manufacturing capacity is largely concentrated in mainland China and elsewhere in East Asia. The United States also believes technologies could be misused or abused by what it views as authoritarian countries such as China.

The meeting was also a chance for the leaders to update their efforts to meet their goal of delivering 1 billion doses of coronavirus vaccines by the end of 2022 to Southeast Asia and elsewhere, with investments in Indian vaccine production capacity.

The commitment was initially made during the first-ever Quad summit meeting in March, but uncertainties had emerged after India was hit by a surge of coronavirus cases with the spread of the highly contagious Delta variant, which forced the country to halt vaccine exports in a bid to inoculate its population.

The Quad confirmed that its efforts are "on track," welcoming India's announcement of a resumption of vaccine exports, beginning in October.

The four countries also reaffirmed their commitment to the complete denuclearization of North Korea, urged Pyongyang to refrain from provocations and called on the country to "engage in substantive dialogue."

The Quad originated in 2004 in response to the Indian Ocean earthquake and tsunami, and there have been times that the framework, denounced by China as an attempt to encircle it, fizzled.

But in recent years, the group has gained traction as a counterweight to Beijing's growing clout in the region amid increasing U.S.-China rivalry.

Building on the efforts of the previous U.S. administration under Donald Trump, the Biden administration has elevated the engagement to the leaders' level as it seeks to rally U.S. allies and like-minded countries to address the challenges posed by China.

Suga, whose visit to the United States will be his final overseas trip before he steps down after just a year in office, met separately with Morrison and Biden on Friday for bilateral talks. According to the Japanese Foreign Ministry, he told the Australian leader that he welcomed the launch of AUKUS, which will involve helping Canberra acquire a fleet of nuclear-powered submarines.

Suga told reporters that the Japan-U.S. alliance has strengthened under his "relationship of trust" with Biden. Suga was the first foreign leader invited to the White House for talks with Biden.

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