(Reuters) - Shares of TikTok U.S. suitors Microsoft Corp, Oracle Corp and Walmart Inc fell on Monday after China’s move to restrict some technology exports spurred worries Beijing might block any deal for the video app’s U.S. assets.

China’s new rules around tech exports mean ByteDance’s sale of TikTok U.S. operations could need approval from Beijing, a Chinese trade expert told state media on Sunday, a requirement that would complicate the forced and politically charged divestment.

Shares of Walmart, Microsoft and Oracle fell between 1.5% and 3% in premarket trading on Monday.

All three pared some of the losses after CNBC reported earlier in the day, giving no details of its sources, that a TikTok deal could be announced as early as Tuesday.

TikTok leaders said in a memo to employees earlier last week that the company was “moving quickly to find resolutions to the issues that we face globally, particularly in the U.S. and India”.

China, however, late on Friday revised a list of technologies banned or restricted for export for the first time in 12 years. Cui Fan, a professor of international trade at the University of International Business and Economics in Beijing, said the changes would apply to TikTok.

“This is clearly directed at slowing down ByteDance’s deal negotiations in this game of high stakes poker,” Wedbush Securities analyst Daniel Ives said.

“With TikTok’s key algorithm at play, ByteDance/TikTok will likely now need to go through a licensing procedure around the need to transfer software code from China to the US.”