SAN FRANCISCO (CBS SF) — Twitter said Wednesday it will close its San Francisco and New York offices because of the rise of the COVID Delta variant.

The decision comes just two weeks after the social media giant began welcoming back its workers after the pandemic shutdown.

READ MORE: One Dead, Three Wounded In Early Sunday Morning Shooting In Oakland's Uptown Neighborhood

Twitter had previously said it would allow workers to work remotely on a permanent basis and required proof of COVID vaccination for employees returning to the office.

READ MORE: No Injuries in Saturday Night Shooting, Santa Rosa Police Say

Twitter is among other tech giants making workplace decisions amid the surge in COVID cases. Also on Wednesday, Google said it would postpone having employees return to their offices and also enacted a mandatory vaccination policy. Facebook announced a similar vaccination policy later on Wednesday.

MORE NEWS: Widespread Bay Area Sunday Morning Power Outages Affecting Thousands

Apple will begin requiring masks for employees and customers at more than half of its U.S. stores starting Thursday.