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, as part of a Pacific tour.

China, which claims Taiwan as its own territory, opposes any foreign interactions or visits by the island's leaders, especially those involving the United States.

A spokesperson for the U.S. State Department reiterated the U.S. position that transits by high-level Taiwan authorities were routine and "consistent with long-standing practice, the unofficial nature of our relations with Taiwan, and the U.S. One-China policy, which remains unchanged."