Facebook parent company MetaIt said Monday it would require Covid-19 booster shot for employees and is delaying full employee returns to U.S. office until March 28, as Omicron variant revises plans in Silicon Valley.

Meta announced Monday that it had delayed its return-to office date to make employees more flexible during the pandemic. Before Jan. 31, the company had planned to reopen all offices to vaccinated workers. The company’s headquarters is in Menlo Park.

We are focusing on making sure that our employees have the freedom to choose where they work in light of current COVID-19 conditions. “We understand that it is difficult to decide where to work due to the uncertainty,” Janelle Gale (Meta VP of Human Resources) said in a statement.

According to the company, employees can request Meta to defer their work from mid-March if they wish to work remotely. The deferrals are for three to five years.

Meta, along with its Silicon Valley neighbors, has had to delay their plans for a return to work due to the Omicron version of Covid-19. However Meta was the first company to inform employees that they will need to show proof of having received a booster shot in order to be allowed to work at the office.

Apple told employees last monthIt did not know a date for its return to the office. Google parent Alphabet was presiding over the December meeting.ushed back its Jan 10. return date indefinitelyTill workers are able to return to “stable, long term” working environments.