Tesla CEO Elon Musk has taken a hardline stance against his employees working from home, Electrek and Bloomberg report. In an email apparently sent to the company’s executive staff with the subject line “Remote work is no longer acceptable,” the CEO said employees must spend a minimum of 40 hours per week in the office, or else “depart Tesla.” He said this should be a “main Tesla office,” and not a “remote branch office.”

Responding to a screenshot of the alleged email posted to Twitter, Musk did not deny its authenticity, and wrote that anyone who disagrees with a policy of coming into the office “should pretend to work somewhere else.” Tesla did not respond to The Verge’s request for comment, but is widely reported to have dissolved its press office.

In his email, the CEO added that he would be willing to consider requests to work remotely under some circumstances, but indicated that such requests would have to be “exceptional” to be approved. “If there are particularly exceptional contributors for whom this is impossible, I will review and approve those exceptions directly,” he wrote. Working 40 hours in person, he said, is “less than we ask of factory workers.”

In a follow-up email seen by Electrek, the CEO claimed his own history of almost living in the Tesla factory was the reason behind the company’s survival. “The more senior you are, the more visible must be your presence,” he wrote. “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.”

After the global pandemic forced many companies to rapidly introduce remote working policies, many are now assessing how they should bring their employees back into the office, or whether they even need to in the first place. Some, such as Apple, are testing a hybrid approach that involves employees coming into the office for just part of the week.

Tesla’s hardline stance makes it a relative outlier in the so-called “new normal.” “If you don’t show up, we will assume you have resigned,” Musk wrote. You can read both of his emails in their entirety over on Electrek.