Chinese regulators have instructed domestic companies to steer clear of Nvidia Corp.’s H20 artificial-intelligence processor, intensifying concerns first aired over the weekend by state-run media that labelled the chip neither technologically advanced nor secure for national use. Notices sent in recent weeks advise firms to avoid the U.S.-made component, especially in projects involving government or national-security data, sources told Bloomberg and The Information. The guidance escalates a state-media campaign that accused the H20 of harboring potential “backdoors” that could permit remote tracking or shutdown by foreign actors. Outlets affiliated with China Central Television and the People’s Daily warned consumers they “have the option not to buy” a product they called unsafe and environmentally unfriendly. Regulators have gone further by ordering technology giants including ByteDance, Alibaba Group and Tencent Holdings to suspend new H20 purchases pending a security review, according to people briefed on the directives. The instructions also question why companies would buy the U.S. chip instead of domestically produced alternatives. The move threatens Nvidia’s efforts to revive sales in its largest overseas market just weeks after Washington lifted a year-old ban on H20 exports in exchange for the company handing 15 percent of related revenue to the U.S. government. Nvidia’s shares dipped modestly in pre-market trading after the reports. In a written response, Nvidia said the H20 "is not a military product or for government infrastructure" and reiterated that the processor contains no backdoors. Beijing’s investigation underscores the growing security and industrial-policy cross-currents confronting U.S. chipmakers as both Washington and Beijing seek greater control over advanced semiconductor supply chains.