WASHINGTON, March 7 (Reuters) - The U.S. House Energy

and Commerce committee on Thursday is set to vote on legislation

giving China's ByteDance six months to divest from short video

app TikTok or face a U.S. ban.

Lawmakers hope to move quickly on the measure and said the

U.S. House of Representatives could take up the bill in the

coming weeks, a move that represents the first significant

momentum for a U.S. crackdown on TikTok, which about 170 million

U.S. users.

Before the vote, lawmakers were getting a closed-door

classified briefing on national security concerns about TikTok's

Chinese ownership.

Representative Mike Gallagher, the Republican chairman of

the House select China committee, and Representative Raja

Krishnamoorthi, the panel's top Democrat, on Tuesday introduced

legislation to address national security concerns posed by

Chinese ownership of the app.

"TikTok could live on and people could do whatever they want

on it provided there is that separation," Gallagher said, urging

U.S. ByteDance investors to support a sale. "It is not a ban -

think of this as a surgery designed to remove the tumor and

thereby save the patient in the process."

TikTok users were flooding Capitol Hill with phone calls

urging lawmakers not to back the measure, congressional aide

said.

Asked if the bill could impact the U.S. operations of

Tencent's ( TCTZF ) WeChat, which then President Donald Trump

sought to ban in 2020, Gallagher said he would not speculate but

said "going forward we can debate what companies fall" under the

bill.

The bill would give ByteDance 165 days to divest TikTok; if

it did not, app stores operated by Apple ( AAPL ), Google

and others could not legally offer TikTok or provide

web hosting services to ByteDance-controlled applications.

"This bill is an outright ban of TikTok, no matter how much

the authors try to disguise it," a company spokesperson said.

"This legislation will trample the First Amendment rights of 170

million Americans and deprive 5 million small businesses of a

platform."

White House press secretary Karine Jean-Pierre on Wednesday

praised the proposal, saying the administration wants "to see

this bill get done so it can get to the president's desk."

The app is popular and getting legislation approved in an

election year may be difficult. Last month, Democratic President

Joe Biden's re-election campaign joined TikTok.

Democratic Senator Mark Warner, who proposed a separate bill

last year to give the White House new powers over TikTok, said

he had "some concerns about the constitutionality of an approach

that names specific companies" but will take "a close look at

this bill."

A U.S. judge in late November blocked Montana's first-of-its

kind state ban on TikTok, saying it violated the free speech

rights of users.

The U.S. Treasury-led Committee on Foreign Investment in the

United States (CFIUS) in March 2023 demanded that TikTok's

Chinese owners sell their shares or face the possibility of the

app being banned, Reuters reported, but the administration has

taken no action.

TikTok says it has not and would not share U.S. user data

with the Chinese government.

The new bill is aimed at bolstering the legal authority to

address TikTok. Biden's predecessor, Republican Donald Trump,

tried to ban TikTok in 2020 but was blocked by U.S. courts.