REDMOND, Washington -- Microsoft told employees Thursday that it has indefinitely delayed their return to U.S. offices until it's safer to do so.

       “Given the uncertainty of COVID-19, we’ve decided against attempting to forecast a new date for a full reopening of our U.S. work sites," Jared Spataro, a corporate vice president, wrote in a blog post.

       Microsoft had already postponed its planned return to the workplace from September to no earlier than Oct. 4, but now says the re-opening won't be next month.

       Microsoft employs about 181,000 full-time workers, of whom 103,000 are in the U.S.

       Microsoft will wait for public health guidance on when it is safe to return, Spataro said. It will then give workers a 30-day transition period to prepare.

       Last month Microsoft said it will require proof of vaccination for all employees, vendors and visitors to its U.S. offices starting this fall.

       The tech giant has made a big push since the pandemic emerged to tailor its suite of workplace software products to homebound workers and timed its delayed re-opening announcement with a number of new product features.

       A hybrid approach permitting employees to toggle between remote and in-office work has been widely embraced in the technology industry, particularly among the largest companies with the biggest payrolls.

       Many tech companies had plans for bringing back most of their workers around Labor Day weekend, but Apple, Google, Facebook, Amazon and a growing list of others have already decided to wait until next year.