The Trump administration on Tuesday announced a ban on new foreign-made humanoid robot imports to the US over "unacceptable risks" to America's national security. The move applies to advanced robots - including humanoid and four-legged machines. The BBC has contacted major Chinese robot manufacturers Unitree, UBTech and AgiBot for comment. Chinese technology firms have rapidly developed humanoid robots to be used in settings including factories and homes. Companies have also been quick to market their machines to businesses and the public ahead of US humanoid robot rivals like Elon Musk's Tesla and Boston Dynamics.