BREAKING: Elon Musk issues ultimatum, commit to ‘hardcore’ Twitter or get out

A midnight internal email from the social media platform's new owner, obtained by the Washington Post, was titled "A Fork in the Road" in the subject line.

"Going forward, to build a breakthrough Twitter 2.0 and succeed in an increasingly competitive world, we will need to be extremely hardcore. This will mean working long hours at high intensity," Musk wrote in the email, which appeared to have been sent to all employees.

"Only exceptional performance will constitute a passing grade," he said.

The Tesla and SpaceX CEO went on to describe how the platform will be "much more engineering-driven," and then handed down the ultimatum.

"If you are sure that you want to be part of the new Twitter, please click yes on the link below,” he wrote before inserting a link to an online survey form.

Anyone who did not sign the pledge by 5 pm on Thursday would get a three-month severance package, he said.

The memo comes as Musk makes sweeping layoffs, particularly of employees who used company messaging channels to speak negatively about their new boss.

One former employee was terminated via Twitter on Monday, seemingly for calling out Musk on a technological issue in public rather than in private.

"Whatever decision you make, thank you for your efforts to make Twitter successful," Musk wrote in the email.