Tesla CEO Elon Musk is warning all executives at the electric car company that they risk being fired if they don’t show up at the office for at least 40 hours per week.

“In a leaked email sent to workers with the miss-spelt subject line ‘remote work is no longer acceptble’, Musk wrote that any executive staff who wish to work remotely must be in the office for a minimum of 40 hours per week ‘or depart Tesla,’” the Daily Mail reported. “He added that the requirement for executive staff to work at least 40 hours in the office is ‘less than we ask of factory workers.’”

“If there are particularly exceptional contributors for whom this is impossible, I will review and approve those exceptions directly,” he wrote, adding that the workplace “must be a main Tesla office, not a remote branch office unrelated to the job duties, for example being responsible for Fremont factory human relations, but having your office in another state.”

Replying to someone who questioned the edict on Twitter, Musk wrote: “They should pretend to work somewhere else.”