San Francisco, Aug 4 (IANS): As the US witnesses a surge in Covid cases, Microsoft has told employees and vendors that starting from next month, they will need to show a proof of vaccination before entering any office building in the US.

The tech giant has also pushed its full office reopening date from September to "no earlier than October 4th, 2021," reports the Verge.

"Starting in September, we'll also require proof of vaccination for all employees, vendors, and any guests entering Microsoft buildings in the US, and will have an accommodation process in place for employees," the company said in a statement.

"We continue to review the situation on a local basis in each region/country/state where we work and will adjust dates and policies as needed".

The Microsoft's decision comes after Facebook asked all US employees to wear masks in offices and told them to get vaccinated when they return to offices.

Facebook said last week that it would require its US employees to be vaccinated against Covid-19 when they return to the office.

The Covid-19 cases have increased in the US, even as vaccination rates grow amid concern over the highly contagious Delta variant.

The US Centers for Disease Control and Prevention (CDC) said that there were about 72,000 new cases per day.

Twitter has shut offices in US, and Google and Alphabet CEO Sundar Pichai said the company will require employees to be vaccinated before returning to the office in the later part of the year.

Apple now requires customers and staff at most of its more than 270 US retail stores to wear masks even if they are vaccinated.