Japan’s decision to join the United States and Netherlands in restricting exports of chipmaking gear to China is giving the allies powerful new weapons to deploy in the escalating technology war.

Japan’s trade ministry said last week that suppliers of 23 types of chip technology will need government approval to export to countries including China as early as July. That affects a broad range of companies that have been central to China’s efforts to build a domestic chip industry, including Tokyo Electron, Nikon and Screen Holdings.

While not as high-profile as their counterparts in the U.S. or Netherlands, Japanese companies control key steps in the semiconductor supply chain, which could be used as potential chokepoints against China. Screen, for instance, is the leading producer of wafer cleaning equipment. Lasertec is the sole supplier of machines needed to inspect designs for the world’s most advanced chips, using extreme ultraviolet lithography chipmaking.