The United States has announced a suite of new commitments in an effort to boost its relations with Pacific Island countries during the Forum Leaders' Meeting taking place in Suva.

US vice-president Kamala Harris will join regional leaders virtually on the second day of the annual meeting on Wednesday at the invitation of Pacific Island Forum chair Frank Bainimarama.

The commitments included the establishment of embassies in Kiribati and Tonga, tripling the funding for economic development and ocean resilience, the appointment of the first-ever US envoy to the Pacific Islands Forum, and developing a new US national strategy on the Pacific.

It would also include expanding USAID presence, bringing Peace Corps back to the region, and establishing the Partners in the Blue Pacific initiative - a new cooperation mechanism including allies Australia, New Zealand, Japan and the United Kingdom.

"This milestone reflects the United States' robust and growing commitment to the Pacific Islands region," the White House said in a statement.

It said Partners of the Blue Pacific, or PBP, was dedicated to supporting Pacific priorities more effectively to bolster Pacific regionalism, and to expand opportunities between the Pacific and the world.

Under the deal, the US and its allies would provide a combined $2.1 billion in development assistance for the region, it said.

The White House said the PBP would also seek to drive additional focus and resources by welcoming further members and observers, including in Europe and the Indo-Pacific.

"Above all, at every stage, the PBP will be led and guided by the Pacific Islands, including close consultations on its flagship projects," it added.

The US was a dialogue partner of the PIF, along with 20 other countries, including China, the European Union, Japan, South Korea, Canada, India, Singapore and the United Kingdom.

The 51st Forum Leaders' Week does not have an in-person Dialogue Partners meeting after Fiji, which is the Forum chair, decided to exclude partners to allow Pacific leaders to focus on resolving internal issues.