Microsoft's search engine Bing could not be accessed in mainland China as of Thursday morning local time. That marks the apparent blocking of the last major non-Chinese search platform that had been operating there.
According to a report from the FT, which cited two unnamed sources, that blockage came on the order of the government.
"We've confirmed that Bing is currently inaccessible in China and are engaged to determine (our) next steps," a Microsoft spokesperson confirmed in an email to CNBC.
Accessing the cn.bing.com website within China resulted in the message: This site can't be reached.
The internet is heavily censored in China as a form of information control. Many non-Chinese websites and social media services such as Twitter and Facebook are blocked.
The reported blockage of Microsoft's Bing comes at a time when the U.S. and China are locked in a long-running trade dispute, with market participants increasingly concerned that the conflict could spill over into a so-called "tech war."
On Tuesday, the former deputy governor of the People's Bank of China, Zhu Min, told CNBC that Beijing could completely cut investment into the Silicon Valley after the intense scrutiny of Huawei, the world's largest telecom equipment maker.
Concerns about the security of privately-held Huawei's technology have intensified, and deteriorated further after the arrest of its chief financial officer, Meng Wanzhou, in Canada late last year.
Meng, who was detained at the request of Washington over allegations that the company violated American sanctions on Iran, was released on bail but still faces the possibility of extradition to the U.S.
The U.S. and other countries — including Canada, Germany, Britain and Australia — accuse China of technology theft and have blocked Huawei's equipment from sensitive infrastructure projects. Beijing denies those allegations.
China has openly declared its intent to become a world tech leader over the next decade, investing hundreds of billions of dollars in technologies like Artificial Intelligence and autonomous vehicles.
— CNBC's Evelyn Cheng and Sam Meredith contributed to this report.