The announcement comes amid a spike in COVID-19 cases due in large part to the surge in Delta variant cases and rampant anti-vaccination sentiment.
Many companies are slowing their reopens due to updated guidance from the Centers for Disease Control and Prevention which recommends indoor masks even for people who have received one of the vaccines.
“After careful consideration of the updated CDC guidelines, and in light of current conditions, Twitter has made a decision to close our open offices in New York and San Francisco as well as to suspend future reopens, effective immediately.” Twitter said, according to The Chronicle of San Francisco.
The social media company had just reopened its offices two weeks ago, the Chronicle said.
Twitter was one of many tech companies to announce that it allowed workers to work remotely indefinitely.
Google said on Wednesday it was delaying its reopening until at least October and forcing employees to get vaccinated against COVID-19.