San Francisco, Nov 18 (IANS): After telling Twitter employees to be "extremely hardcore" at work or quit, Elon Musk has sent another email to them, this time daring managers to approve remote work "at their own risk".

The new email, seen by The Verge, also told employees to do in-person meetings, as a disabled employee has sued Twitter over its ban on remote work.

"Regarding remote work, all that is required for approval is that your manager takes responsibility for ensuring that you are making an excellent contribution," Musk wrote.

"It is also expected that you have in-person meetings with your colleagues on a reasonable cadence, ideally weekly, but not less than once per month," he added.

The email further said that "at the risk of stating the obvious, any manager who falsely claims that someone reporting to them is doing excellent work or that a given role is essential, whether remote or not, will be exited from the company".

Earlier, bringing his Tesla way of work style to Twitter, Musk had given employees ultimatum till Thursday that they have to perform "extremely hardcore" work or leave the micro-blogging platform.

The new Twitter CEO said that any employee who did not agree to the ultimatum will receive three months' severance.

There were reports of Twitter employees sleeping on the floor at the office after Musk took over the company.

Musk has earlier said he's worked as much as 120 hours a week at times and has slept on the floor at a Tesla factory.

He has fired at least 20 employees at Twitter who criticised his actions either on Twitter or on internal messaging platform Slack, and even some were sacked just for retweeting posts slamming the new Twitter CEO.