Facebook has admitted cutting-in major Chinese smartphone hardware makers into its personal data-sharing deals - including equipment makers banned from US government networks and military installations over espionage fears.
According to The New York Times, one of those companies is Huawei, which US intelligence authorities have flagged as a potential national security threat due to worries the tech giant could use the data to conduct snooping on behalf of China's government.
The news comes not too long after the revelation that Facebook was sharing user data with phone and hardware makers and, according to the report, the social network says it cut deals with at least four Chinese firms.
The data-sharing deal is somewhat ironic considering that China has banned Facebook use since 2009, blocking easy access to the social network via the so-called Great Firewall of China.
Anyone in China that wants to access Facebook needs to use proxy servers and VPNs to get around the restrictions, but the increasingly authoritarian government of President Xi - recently made president for life - has also sought to clampdown on their use.
"Facebook's integrations with Huawei, Lenovo, Oppo and TCL were controlled from the get go — and we approved the Facebook experiences these companies built," Francisco Varela, the company's vice president of mobile partnerships, said in a statement.
"Given the interest from Congress, we wanted to make clear that all the information from these integrations with Huawei was stored on the device, not on Huawei's servers."
Huawei said in an emailed statement that it never collected or stored Facebook user data but had worked in the past with the social media company to make services "more convenient for users."
Given that Facebook is under an increasing level of scrutiny in the aftermath of the Cambridge Analytica affair, such revelations over data-sharing partnerships and practices come as a bad time for the social network.
However, users show little sign of dumping the platform in any great number in response.
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