A former top Chinese trade adviser warned that export trade controls put in place by China are “just a beginning” of their economic plans, ahead of a scheduled visit to the country from Treasury Department Secretary Janet Yellen. Former Vice Minister of Commerce Wei Jianguo told China Daily, a Chinese government-run outlet, Wednesday that Beijing is prepared to place additional trade restrictions on metals used in semiconductors if the United States hits China with tougher technology restrictions. “This is just the beginning of China’s countermeasures, and China’s tool box has many more types of measures available,” Wei said. “If the...