New owner Elon Musk is expected to reduce the Twitter’s workforce of 8,000 by as much as half.
An internal email said the cuts were designed to put Twitter on a “healthy path” as the platform struggles to make a profit.
All staff are set to receive an email with the subject “Your Role at Twitter.”
A class action lawsuit has already been filed against the company over the mass job cuts and the amount of notice given.
Tesla and SpaceX owner Musk bought the social media platform in a $44bn (£39.3bn) deal last week after a protracted process.
He has already removed the entire board and is now the sole executive.