China has protested to the United States over a stopover by Taiwanese President Tsai Ing-wen during which she toured the National Aeronautics and Space Administration in Houston. Tsai made the visit while returning from a trip to Paraguay and Belize, two of only 18 countries extending diplomatic recognition to Taiwan, AP reported. Chinese Foreign Ministry spokesman Lu Kang said on Monday that Beijing would “always oppose any country providing conveniences and venues for relevant people from Taiwan to conduct such activities.” Tsai also spoke at the Ronald Reagan Presidential Library in California while in transit last week. It was the first public address made by a Taiwanese leader in the US in more than a decade.