By Devin Fehely

SAN FRANCISCO (KPIX 5) — Millions of users of the WeChat social media and messaging platform are bracing for the possible Sunday shut down the app, fearing it will effectively sever lines of communication with family and friends in China.

“My two daughters and I do a weekly call with my parents who are in China,” explained Josephine Zhao. She says the Chinese government blocks most U.S. social media platforms like Facebook, making WeChat the preferred means of communicating with family and friends in China.

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“We have been relying on WeChat for the past few years as the only, sole way of communication,” said Zhao.

Citing security concerns, the Trump administration is planning to ban new downloads and future updates of both WeChat and TikTok by this Sunday. But the administration’s actions regarding WeChat go a step further, blocking its money transfer and mobile payment features and restricting its access to the internet.

“In the case of WeChat, it’s just over. It’s shut down. The servers to house all of the data have to be removed from the U.S. So even if people have it on their phones and want to use it, it will be really delayed,” said  CNET analyst Shara Tibken.

The company estimates WeChat has a billion users worldwide — the overwhelming majority in China. It combines elements of popular social media, messaging and financial services companies like Messenger, Facebook, Apple Pay or Venmo and FaceTime.

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“I have two friends who are in China right now. And when they remove WeChat, I wouldn’t be able to communicate with them. And that would be really, really sad,” said WeChat user Dat Huynh.

Many users like UC Riverside instructor Michael Toothman warn the potential fallout from a shutdown of the app in the U.S. could be far wider than most imagine.

“It’s very concerning. I’ve probably had 25 messages from my students and former students in China. They’re very concerned about how they’ll communicate with me because they have no other way,” said Toothman.

In China, WeChat Is woven into the fabric of virtually every aspect of people’s lives. Professor Toothman says he is very concerned about the potential unintended consequences for American companies with business in China.

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He says those companies will just have to wait and see if WeChat is racing toward a Sunday deadline or a last-minute deal.