(Bloomberg) -- Google has threatened to reduce pay or even fire staff who fail to comply with internal policies on Covid 19 vaccinations, CNBC reported, citing internal documents.

The Alphabet Inc. unit warned employees they had till Dec. 3 to declare and prove their vaccination status, or apply for exemptions. Those who hadn’t complied by Jan. 18 will be placed on “paid administrative leave” for 30 days, CNBC said. They could then be put on unpaid leave for up to six months, before finally getting dismissed, it added.

Like much of the U.S., Silicon Valley is coping with a resurgence in Covid 19 and the new omicron variant, forcing companies to re-evaluate plans to get staff to return to offices. The Biden administration has mandated vaccinations for federal contractors nationwide, but several major U.S. corporations have suspended efforts to comply amid a slew of challenges from states that say the president overstepped his authority in requiring Covid-19 shots.

Google, which employs more than 150,000 in the country, said it plans to follow Biden’s order. In July, the search giant said it will require all workers returning to work to get vaccinated. Representatives for the company didn’t immediately respond to a request for comment.

“We expect that almost all roles at Google in the US will fall within the scope of the executive order,” CNBC reported, citing Google’s memo. “Anyone entering a Google building must be fully vaccinated or have an approved accommodation that allows them to work or come onsite,” the company said, adding that “frequent testing is not a valid alternative to vaccination.”

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