The companywide ultimatum comes after Musk fired key Twitter executives, laid off half of Twitter’s full-time employees, and slashed the number of contractors working with the company without notice.

New Twitter CEO Elon Musk has told remaining employees of the social media company that they must commit to working “long hours at high intensity” or receive “three months of severance” if they refuse to consent to his conditions.

In an email sent to the company’s staff on Wednesday, Musk said they should agree to the pledge if they wanted to stay or leave if they cannot support his vision for “Twitter 2.0”, adding that those who do not sign up by Thursday will be given three months’ severance pay.

In the companywide ultimatum issued to staff around midnight in San Francisco time, the sole director said Twitter “will need to be extremely hardcore” in order to succeed, and “This will mean working long hours at high intensity. Only exceptional performance will constitute a passing grade.”

Musk told his employees that they needed to click on a link by 17:00 EST on Thursday if they want to be “part of the new Twitter” and further added that “Whatever decision you make, thank you for your efforts to make Twitter successful.”

The world’s richest man has already announced that half of Twitter's staff are being let go after he bought the company in a $44bn (£38.7bn) deal.

According to him, he had “no choice” over the cuts as the company was losing $4m (£3.51m) a day. He blamed “activist groups pressuring advertisers” for a “massive drop in revenue”.

A host of top Twitter executives have also stepped down following his purchase of the firm.

Last week saw the entrepreneur telling the company’s staff that remote working would end as “difficult times” lay ahead.

According to Bloomberg, Musk, in an email sent to staff, said employees would be expected in the office for at least 40 hours a week. He said there was “no way to sugar coat the message” that the slowing global economy was going to hit Twitter's advertising revenues.

This week saw the Twitter boss firing veteran engineers at the company after they criticised him in public, or in the company’s internal Slack channels.