A bipartisan group of U.S. lawmakers introduced legislation on Tuesday to give China’s ByteDance about six months to divest popular short video app TikTok or face a U.S. ban, seeking to tackle national security concerns about its Chinese ownership.

The bill is the first significant legislative move in nearly a year toward banning or forcing ByteDance to divest the popular app, after senate legislation to ban it stalled in Congress last year in the face of heavy lobbying by TikTok.

Mike Gallagher, the Republican chair of the House of Representatives’ select China committee and Representative Raja Krishnamoorthi, the top Democrat, are among more than a dozen lawmakers introducing the measure, which is expected to see an initial vote on Thursday.

“This is my message to TikTok: break up with the Chinese Communist Party or lose access to your American users,” Gallagher said. “America’s foremost adversary has no business controlling a dominant media platform in the United States.”

The bill would give ByteDance 165 days to divest TikTok, which is used by more than 170 million Americans, or make it unlawful for app stores run by Apple, Google and others to offer TikTok or provide web hosting services to apps controlled by ByteDance.

A White House National Security Council spokesperson called the bill “an important and welcome step” adding that the Biden administration would work with Congress “to further strengthen this legislation and put it on the strongest possible legal footing.”