Amazon.com Inc will not require fully vaccinated U.S. warehouse employees to wear masks at work from Tuesday unless mandated by state or local law, a source familiar with the matter said.

The e-commerce giant had in August ordered U.S. employees to wear a mask at work regardless of their vaccination status due to the spread of the highly infectious Delta variant of COVID-19.

The variant had also prompted other major tech companies, including Facebook Inc, Google and Microsoft Corp, to tighten their defenses against COVID-19.

Amazon's decision comes just before the crucial holiday season, for which it has been hiring thousands of hourly workers by offering them sign-up bonuses in a tight job market. CNBC first reported the news.