Elon Musk warned Twitter Inc (NYSE:TWTR) staff they face lay-offs if his US$44bn acquisition of the social media site succeeds.
Using video link, the billionaire entrepreneur spoke directly to Twitter's 7,500 employees on Thursday.
The former richest man in the world said he will perform a "rationalisation of headcount" once he becomes the boss.
Musk also insisted he will clamp down on staff working from home, saying only "excellent contributors" can work remotely, Bloomberg reported.
"Trust is as trust does. I tend to be extremely literal in what I say... One does not (need) to read between the lines. One can simply read the lines," Musk said in the meeting, according to a tweet from Twitter's head of brand experiences and engagement, Nola Weinstein.
The tweet was subsequently deleted, as were all other tweets from Weinstein about the meeting.
The Tesla boss said he plans to grow Twitter to 1bn users, up from the current 229mln users, claiming the total could be met within the next decade.
Musk made the virtual appearance after weeks of uncertainty for Twitter employees after he tweeted the deal was "on hold" while he investigates the number of bots on Twitter.
Musk also said Twitter users should be able to post "pretty outrageous things" as long as they stay within the law.
Twitter admits 5% of its 229mln active accounts are bots, but the billionaire has challenged this figure.
An employee at Twitter who spoke to Reuters described Musk's hour-long call as "rambling," adding Musk closed the call by saying he has seen "no actual evidence" of alien life forms.