(Bloomberg) -- Alphabet Inc.’s Google is once again pushing back the date it will require employees to return to U.S. offices on renewed concern after cases of the Covid-19 omicron variant have been confirmed, executives told employees on Thursday.  

Google had set Jan. 10 as its return date, asking a bulk of its workforce to come in three days a week. Chris Rackow, a Google vice president of security, emailed U.S. staff on Thursday that the company was “going to wait until the new year to assess” a full return, according to a message viewed by Bloomberg News. CNBC earlier reported the news.

The Mountain View, California-based company has committed to a “hybrid” system, allowing certain employees to switch offices or work remotely, but encouraging most to return. A Google spokesperson said the company is seeing an increase in staffers voluntarily coming in to company facilities, with almost 40% of U.S. employees arriving into offices in recent weeks.

Earlier Thursday, Google notified employees in Europe, the Middle East and Africa that their return to offices also would be delayed from the planned Jan. 10 date. 

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