The foreign ministers of Japan, the United States, Australia and India vowed Friday to support the protection of national sovereignty and territorial integrity under international law, amid mounting fears Russia could invade Ukraine.

"Quad" major Indo-Pacific democracies "champion the free, open, and inclusive rules-based order, rooted in international law, that protect the sovereignty and territorial integrity of regional countries," they said in a joint statement released after their meeting in Melbourne, Australia.

The gathering was just the third in-person meeting among the four nations' foreign ministers and the first face-to-face meeting since October 2020. It brought together Japanese Foreign Minister Yoshimasa Hayashi, U.S. Secretary of State Antony Blinken, Australian Foreign Minister Marise Payne and Indian Foreign Minister Subrahmanyam Jaishankar.

(From L) U.S. Secretary of State Antony Blinken, Australian Foreign Minister Marise Payne, India's Subrahmanyam Jaishankar and Japan's Yoshimasa Hayashi meet on Feb. 11, 2022, in Melbourne. (Pool photo)(Kyodo)

"One of the reasons we're working so intensely to defend the core principles, threatened by Russia's aggression toward Ukraine, is because those very same principles are crucial to enjoying stability" in the Indo-Pacific region, Blinken told a joint press conference after the meeting.

The Quad gathering came a day after Russia began military exercises in Belarus, further intensifying tensions over Moscow's military buildup near the Ukrainian border.

Blinken said a Russian invasion could begin "at any time," including during the ongoing Beijing Winter Olympics, which runs through Feb. 20.

While Payne and Hayashi stood aligned with Blinken by showing their support for Ukraine, Jaishankar seemed to strike a softer tone regarding Russia, saying that the Quad group is "for something, not against somebody."

The foreign ministers also implicitly expressed their concerns over China, which has become increasingly assertive in its territorial claims in the East and South China seas.

The Quad members reaffirmed their commitment to backing the efforts of nations to advance a free and open Indo-Pacific, saying that the region is where they can strive to protect the interests of their people "free from coercion."

Earlier at the beginning of the meeting, Hayashi said the four nations can "play a big role" at a time when "the existing international order has been challenged in various fields."

Payne said in her opening remarks that the group aims to act to support an Indo-Pacific region "where sovereign states can exercise their own strategic choices free from coercion so that their people are able to pursue prosperity."

Tokyo and Washington have repeatedly opposed what they call "any unilateral attempts to change the status quo" by force in the East China Sea, where the Japan-controlled, China-claimed Senkaku Islands are located, and Beijing has been increasing its military clout.

China, which has been wary of the Quad dialogue, was quick to criticize Friday's meeting, with Foreign Ministry spokesman Zhao Lijian blasting it as a "tool to contain China and maintain U.S. hegemony."

The Quad mechanism has been "artificially provoking confrontation and undermining international solidarity," Zhao told reporters in Beijing, adding the four countries should abandon their "Cold War mentality" for peace and stability in the region.

As for North Korea, which has made a barrage of missile firings since the beginning of this year, the ministers condemned its "destabilizing ballistic missile launches." The Quad group confirmed their commitment to complete denuclearization of the Korean Peninsula, the statement said.

The foreign ministers also aired grave concern about a humanitarian crisis in Myanmar, which has been mired in political turmoil since the military seized power in a coup last February. They called for "an end to violence, the release of all those arbitrarily detained, including foreigners, and unhindered humanitarian access."

To bolster efforts to counter the coronavirus pandemic, the top diplomats agreed to assist developing nations in training health care workers and enhancing their infrastructure to deliver COVID-19 vaccines to hard-to-reach areas.

The four nations also pledged to promote their cooperation in areas such as counterterrorism, cybersecurity and countering disinformation.

The talks will pave the way for a summit meeting of the four nations that Japanese Prime Minister Fumio Kishida and U.S. President Joe Biden had agreed to hold in Japan in the first half of 2022. The statement said the ministers "look forward" to Japan hosting the next Quad summit.

The Quad group's last in-person meeting in October 2020 was held in Tokyo. It was followed by virtual talks in February 2021 due to the pandemic.

After the meeting, Hayashi and Blinken are scheduled to head for Hawaii to attend a meeting on Sunday that will also involve South Korean Foreign Minister Chung Eui Yong.

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