According to an email written to Tesla employees on Tuesday night, CEO Elon Musk has asked them to return to the office or leave the company. In the email, Musk stated, “Everyone at Tesla is required to spend a minimum of 40 hours in the office every week.” “If you don’t show up, we will assume you have resigned.”

In the face of employee resistance and a resurgence of coronavirus infections, major Silicon Valley tech corporations do not demand workers to return to the office full-time.

Tesla‘s headquarters are now in Austin, Texas, while one of its factories and engineering center is still in the San Francisco Bay area.

“There are of course companies that don’t require this, but when was the last time they shipped a great new product? It’s been a while,” Musk said in the email. “Tesla has and will create and actually manufacture the most exciting and meaningful products of any company on Earth. This will not happen by phoning it in.”

Another email sent by Musk to executives, according to one of his Twitter followers, asked them to work in the office for at least 40 hours a week or “depart Tesla.”

“They should pretend to work somewhere else,” the billionaire, who has agreed to take Twitter Inc private in a $44 billion deal, said in response to this post.

Musk violated Alameda County’s lockdown procedures to stop the spread of the coronavirus by reopening a Tesla facility in Fremont, California, in May 2020, according to Reuters.

According to county statistics collected by the legal information portal Plainsite, Tesla reported 440 cases at the factory from May to December 2020.

According to county data, Musk‘s SpaceX firm reported 132 COVID-19 cases at its headquarters in Hawthorne, a Los Angeles city.

While some big employers have embraced voluntary work-from-home policies permanently, others, including Alphabet Inc’s Google, are betting that it is best to push in-person interactions among colleagues.