Chinese mobile phone maker Huawei said on Wednesday it has never collected or stored Facebook user data, after the social media giant acknowledged it shared such data with Huawei and other manufacturers.

Huawei, a company flagged by US intelligence officials as a national security threat, was the latest device maker at the center of a fresh wave of allegations over Facebook’s handling of private data.

Chinese firms Huawei, Lenovo, Oppo and TCL were among numerous handset makers that were given access to Facebook data in a “controlled” way approved by Facebook, the social media giant’s vice president of mobile partnerships, Francisco Varela, said in a statement on Tuesday.

The statement came after The New York Times published reports detailing how Facebook has given device makers deep access to the data of users’ friends without their explicit consent. The data included work history, relationship status and likes on device users and their friends.

In a follow-up report, The Times said the recipients of Facebook data included Chinese firms like Huawei that have long been labeled a national security threat by Congress. Facebook told the newspaper it would end its data partnership with Huawei by the end of this week.

Senator Mark Warner, the top Democrat on the Senate Intelligence Committee, said the news raises legitimate concerns and wanted to know how Facebook ensured data was not transferred to Chinese servers.

“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,” Facebook’s Varela said Tuesday.

Huawei said its cooperation with Facebook was aimed at improving services for its users.

“Like all leading smartphone providers, Huawei worked with Facebook to make Facebook’s services more convenient for users,” Huawei spokesman Joe Kelly said in a text message on Wednesday, adding that Huawei “has never collected or stored any Facebook user data”.

Hua Chunying, a Chinese Foreign Ministry spokeswoman, declined to comment on the issue but said: “We hope the US can provide a fair, transparent, open and friendly environment for Chinese companies’ operation and investment.”

The company, founded by former Chinese military officer Ren Zhengfei, has long denied that its products pose security risks even as it grew into the world’s largest telecom equipment provider and a leading phone manufacturer — behind only Apple and Samsung.

Huawei and its Shenzhen-based rival ZTE have been the subject of security misgivings in the US for years, but they have come under particular scrutiny since the start of the Trump administration amid rising US-China tensions on a range of subjects.

The Pentagon in May banned the sale of Huawei and ZTE phones on military bases, four months after AT&T dropped a deal to sell a new Huawei smartphone.