The Chinese government could use TikTok to control data on millions of people and harness the short-form video app to shape public opinion should China invade Taiwan, FBI Director Christopher Wray told the Senate Intelligence Committee Wednesday.

Wray responded affirmatively to questions from Republican Sen. Marco Rubio of Florida, the panel's ranking member, on whether TikTok would allow Beijing widespread control over data and a valuable influence tool in the event of war in the Taiwan Strait.

"The most fundamental piece that cuts across every one of those risks and threats that you mentioned that I think Americans need to understand is that something that's very sacred in our country 鈥攖he difference between the private sector and public sector 鈥� that's a line that is non-existent in the way that the CCP [Chinese Communist Party] operates," Wray told Rubio in the hearing.

Rubio, the top Republican on the Senate panel, argued that TikTok presents "a substantial national security threat for the country of a kind that we didn't face in the past."

Wray's comments come a day after Gen. Paul Nakasone, head of the U.S. National Security Agency, told the Senate Armed Services Committee that he worried TikTok could censor videos to shape public opinion in a way that threatens U.S. national security interests.

It's the latest in a full-court press from US officials to sound the alarm about TikTok's alleged security risks as Congress weighs giving the Biden administration more authority to address the alleged threat posed by the platform, up to and including banning the app in the United States

TikTok CEO Shou Chew said this week that the Chinese government has "never asked us for U.S. user data" and the company would not provide it if the government did ask. Chew also said that "misinformation and propaganda has no place on our platform, and our users do not expect that."

The company has taken voluntary steps to wall off U.S. user data from the rest of its global organization, including by hosting that data on servers operated by the U.S. tech giant Oracle. The company is also negotiating a possible agreement with the Biden administration that could allow TikTok to continue operating in the United States under certain conditions.

In a statement this week, a TikTok spokesperson said a U.S. government ban would stifle American speech and would be "a ban on the export of American culture and values to the billion-plus people who use our service worldwide."

-- CNN's Brian Fung and Catherine Thorbecke contributed to this report.