Antony Blinken on Wednesday became the first U.S. secretary of state to visit Tonga, dedicating a new U.S. embassy and warning South Pacific nations about the perils of "predatory" Chinese investment.

As part of a drive to build Washington's influence across the region and to counter Beijing's growing clout, Blinken touched down in Nuku'alofa on a diplomatic charm offensive.

"We're a Pacific nation," and "we very much see the future in the Indo-Pacific region," Blinken told his hosts while pledging support on projects that are important to them.