The U.S. government on Tuesday announced a set of actions to strengthen ties with Pacific island nations amid China's growing clout, such as by opening new embassies and tripling U.S. funding to support the region's economic development.

"We believe that we're now embarking on a new chapter in this longstanding partnership," a senior official of the administration of President Joe Biden said, adding that the United States is "significantly stepping up our game in the Pacific islands."

The new U.S. commitments were unveiled as the leaders of the Pacific Islands Forum, the region's premier political and economic policy organization, hold an annual summit that began Monday.

U.S. President Joe Biden. (Kyodo)

Under the plan, the United States will aim to establish U.S. embassies in Kiribati and Tonga, and secure $60 million per year for the next 10 years -- nearly triple the current levels -- for economic assistance, including combating illegal fishing, enhancing maritime security and strengthening climate resilience.

The Biden administration will also craft a first-ever U.S. strategy on the Pacific islands, which it says will be "a whole-of-government strategy" to prioritize the islands in American foreign policy and drive effective implementation.

The document will be nested under the Indo-Pacific strategy, which was released earlier this year. In the strategy, the Biden administration has vowed to bolster its security and economic role to advance a free and open region, while building "collective capacity" with allies to counter China's growing assertiveness.

The United States has been stepping up efforts to engage with the Pacific island nations, apparently alarmed by Beijing's moves to bolster its influence as seen by the signing of a security pact with the Solomon Islands in April.

The treaty reportedly allows the deployment of Chinese police, military and other armed personnel, as well as the docking of the Asian power's military ships in the islands.

The Pacific Islands Forum comprises 18 members, including Australia and New Zealand. But Kiribati, known to be forging closer ties with China, has reportedly announced its withdrawal from the group ahead of the summit meeting.

The senior U.S. official said the United States is concerned by the report and that it supports talks to keep Kiribati as part of the forum.

The Biden administration also plans to appoint the first-ever U.S. envoy to the Pacific Islands Forum to expand its diplomatic footprint across the islands, according to the official.

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