BEIJING—China vowed strong retaliation if the U.S. imposes newly threatened tariffs on Chinese goods and ruled out engaging in negotiations while Washington is escalating the pressure on Beijing over trade.

President Donald Trump’s announcement late Thursday that he was considering penalties on an additional $100 billion in Chinese goods brought a vehement response from the government. At a hastily-arranged briefing with reporters Friday night, Chinese Commerce Ministry spokesman Gao Feng described the U.S. move as “extremely...