FACEBOOK said it entered an agreement with chinese firms for data shairing including Huawei, a company US intelligence previously flagged as a security threat for has confirmed it has a data-sharing partnership with Chinese firms
The agreements gave the Chinese firms some access to users' data to help them build Facebook "experiences" on their own platforms.
Facebook said all the data collected remained on users' phones not servers.
The company is already under scrutiny over how it uses members' information.
Facebook has been blocked in China since 2009 but the company has been trying to find other ways to access the massive potential market.
The New York Times reported earlier this week that Facebook had given at least 60 device-makers access to users' data - and that of their Facebook friends - without obtaining explicit consent and that in some cases the details were stored on the firms' own servers.
Facebook rejected claims that this had been a breach of privacy pledges that it had made to its members and a US regulator.
Senator Mark Warner, who sits on the US Senate Intelligence Committee, said news that Huawei was among the companies getting the privileged access to the Facebook data raised "legitimate concerns".
Yesterday, Facebook responded by saying it "along with many other US tech companies have worked with them [Huawei] and other Chinese manufacturers to integrate their services onto these phones".