His committee also oversees the Federal Trade Commission, which is investigating Facebook to determine whether the company’s data policies violate a 2011 consent decree with the commission.

Senator Mark Warner of Virginia pointed out that concerns about Huawei were not new, citing a 2012 congressional report on the “close relationships between the Chinese Communist Party and equipment makers like Huawei.”

“I look forward to learning more about how Facebook ensured that information about their users was not sent to Chinese servers,” said Mr. Warner, the top Democrat on the Intelligence Committee.

“All Facebook’s integrations with Huawei, Lenovo, Oppo and TCL were controlled from the get-go — and Facebook approved everything that was built,” said Francisco Varela, a Facebook vice president. “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.”

Banned in China since 2009, Facebook in recent years has quietly sought to re-establish itself there. The company’s chief executive, Mark Zuckerberg, has tried to cultivate a relationship with China’s president, Xi Jinping, and put in an appearance at one of the country’s top universities.

Last year, Facebook released a photo-sharing app in China that was a near replica of its Moments app, but did not put its name on it. And the company has worked on a tool that allowed targeted censorship, prompting some employees to quit over the project.

Still, Facebook has struggled to gain momentum, and in January an executive in charge of courting China’s government left after spending three years on a charm campaign to get the social media service back in the country.