Washington unveiled new sanctions Thursday targeting China-based companies linked to the production of drones that Russia has deployed in its war against Ukraine.It marks the first time the United States sanctionedChinese companies directly developing and producing complete weapons systems in partnership with Russian firms, the United States Treasury Department said.State Department spokesman Matthew Miller said it was the first time we actually saw a Chinese company manufacturing a weapon itself that then was used on the battlefield by Russia.That is why we continue to work with our allies and partners around the world to make clear to China that this practice is unacceptable and they need to take steps to counter it, he added.China and Russia have drawn closer since Moscow launched its full-scale invasion of Ukraine in 2022.Beijing maintains that it is neutral in the conflict, but Western governments including the United States argue that China's diplomatic and economic support helps to sustain Moscow's war of aggression.Beijing hit back against the measures Friday, saying it firmly opposes the United States' illegal unilateral sanctions on Chinese companies and absolutely does not accept its groundless accusations and pressure.China has never provided lethal weapons to any party in the Russia-Ukraine conflict, strictly controls the export of dual-use items including drones, and opposes the use of civilian drones for military purposes, foreign ministry spokeswoman Mao Ning said.China will take all necessary measures to resolutely safeguard the legitimate rights and interests of Chinese companies and citizens, Mao told journalists.The United States Treasury Department's latest sanctions took aim at three companies two in China and one in Russia and a Russian national over their involvement in developing and making Russia's Garpiya series long-range attack drone.The department said the drone was designed and developed by China-based experts, and produced at Chinese factories in collaboration with Russian defense firms.They are then transferred to Russia for use against Ukraine.Russia increasingly relies on the expertise of foreign professionals and the import of sophisticated technologies to sustain its weapons program and advance its military campaign against Ukraine, said Treasury Acting Under Secretary for Terrorism and Financial Intelligence Bradley Smith.Meanwhile, the two China-based companies are Xiamen Limbach Aircraft Engine Co and Redlepus Vector Industry Shenzhen Co.A man who answered a phone call to a number registered with Limbach on Friday said there were problems with the phone signal when an AFP journalist identified himself, before hanging up and not responding to further calls or messages.Redlepus did not respond to phone calls or emails from AFP.Also targeted under the sanctions were Russia-based Limited Liability Company Trading House Vector and Russian citizen Artem Mikhailovich Yamshchikov.Previous United States sanctions have targeted Chinese entities providing components to Russian firms that are later used for weapons weapons.