Beijing voiced "strong dissatisfaction" on Thursday after the United States announced sanctions on Chinese companies for buying Iranian oil.
China, which is embroiled in a trade war as well as myriad other disputes with Washington, is believed to be the biggest foreign buyer of Iranian oil.
Speaking to a pressure group opposed to the Iranian regime on the sidelines of the United Nations, US Secretary of State Mike Pompeo said Wednesday the actions were in response to violations of unilateral US sanctions.
He said sanctions were being placed both on the companies and on their chief executives.
"China expresses strong dissatisfaction and resolute opposition to the sanctions imposed by the United States on Chinese enterprises and individuals," foreign ministry spokesman Geng Shuang said at a regular press briefing on Thursday.
"Despite the legitimate rights and interests of all parties, the United States wielded a wanton stick of sanctions, which is a gross violation of the basic norms of international relations," Mr Geng said.
Trump Vice President Pick JD Vance Urges Voters To "Choose A New Path" "Meat And Potatoes Guy Who Cooks Indian Food": Usha Vance On Husband Joe Biden's Covid Case Delivers Latest Blow to Hard-Luck Campaign Why BJP Lost Lok Sabha Polls In Uttar Pradesh - 6 Reasons In Party Report World's Largest Isolated Tribe Makes Rare Appearance In New Footage Travel Influencer Aanvi Kamdar Dies After Falling Off A Waterfall Near Mumbai Supreme Court Hears NEET Case, Says It Has "Social Ramifications" Watch: Ashneer Grover's Reaction To 22-Year-Old's Monthly Earning Viral IIT Kanpur Introduces 'SATHEE SSC' Platform For Exam Preparation Track Latest News Live on NDTV.com and get news updates from India and around the world.