The Biden administration is keeping up the pressure on Chinese technology firms by adding more companies to a Commerce Department blacklist. Seven Chinese businesses with ties to the military were added to the so-called Entity List on Thursday in a move that restricts US firms from dealing with the companies. All seven of the listed companies, the Department said, operate in the field of supercomputing and have helped the Chinese government modernize its military or have worked on weapons of mass destruction programs. “Supercomputing capabilities are vital for the development of many — perhaps almost all — modern weapons and national security systems, such as nuclear weapons and hypersonic weapons,” said Commerce Secretary Gina Raimondo in a statement. “The Department of Commerce will use the full extent of its authorities to prevent China from leveraging US technologies to support these destabilizing military modernization efforts.” The newly blacklisted companies include Tianjin Phytium Information Technology, Shanghai High-Performance Integrated Circuit Design Center and Sunway Microelectronics, as well as four National Supercomputing Centers in Jinan, Shenzhen, Wuxi and Zhengzhou. The department’s Entity List has existed for years. But during the Trump administration, the US government began adding Chinese businesses to the list at a faster pace, beginning with companies such as Huawei, the global telecommunications giant. The Biden administration is reviewing many of the Commerce Department’s Trump-era policies. So far, officials appear poised to maintain the US government’s confrontational posture toward China. President Biden’s infrastructure plan, for example, highlights the strategic threat posed by China, describing it as a competitor in technology and R&D.