Taiwan’s president set off on a mission on Saturday to shore up relations with some of his island democracy’s shrinking band of diplomatic allies: three tiny Pacific Island nations that have taken an outsize importance in Taiwan’s struggle against Chinese efforts to push it off the international stage.

Taiwan’s president departed for his trip to the South Pacific that will include a two-day transit in the U.S., his first since assuming office, though few details about his itinerary are public.

China urged the United States on Friday to exercise the "utmost caution" on relations with democratically governed Taiwan, ahead of a sensitive trip its President Lai Ching-te starts this week to both Hawaii and Guam,