TAIPEI, Taiwan — Panama has severed diplomatic relations with Taiwan in favor of recognizing China, the latest in a series of developments adding to the island’s isolation on the world stage and raising questions about waning American influence under President Trump.

Panama’s decision handed Beijing a diplomatic victory at a time when Mr. Trump, in hopes of securing cooperation on issues like trade and North Korea’s nuclear ambitions, has retreated from the confrontational stances he took toward China as a candidate.

Mr. Trump’s marked warming toward China since he became president — after a rocky start that included a phone conversation with Taiwan’s president, Tsai Ing-wen — has created a diplomatic vacuum in some regions of the world. That has, in turn, made it even harder for countries like Panama to resist political and economic enticements from China, according to analysts.

Only 19 countries and the Vatican now recognize Taiwan, which is officially known as the Republic of China. Several of those countries are in Central America, including Guatemala, Honduras and Nicaragua, and the decision by Panama, announced on Monday, appeared to put those relationships in doubt.