Twitter has announced to shut its offices in New York and San Francisco in response to the new guidelines issued by the US Centers for Disease Control and Prevention (CDC). The microblogging platform reopened the offices just two weeks ago on July 12.

"Twitter has made the decision to close our opened offices in New York and San Francisco as well as pause future office reopenings, effective immediately," a company spokesperson told TechCrunch on Wednesday.

"We're continuing to closely monitor local conditions and make necessary changes that prioritise the health and safety of our Tweeps," the spokesperson added.

Barely three months after suggesting that vaccinated people no longer needed to wear masks, indoors or out, the US CDC has now recommended people to resume wearing masks amid the surging Delta variant.

The new guidance advised that people who live in high-transmission communities wear masks in indoor public spaces, even if they've been vaccinated. It is also recommended that vaccinated people with vulnerable household members, including young children and those who are immunocompromised, wear masks indoors in public spaces.

Other tech companies also took cognizance of the new CDC guidelines. Google and Alphabet CEO Sundar Pichai said the company will require employees to be vaccinated before returning to the office in the latter part of the year.

From Thursday, Apple will require customers and staff at most of its more than 270 US retail stores to wear masks even if they are vaccinated.

Facebook and Amazon have also confirmed similar policies around vaccination and wearing masks. Facebook will require its US employees to be vaccinated against COVID-19 when they return to the office.

"As our offices reopen, we will be requiring anyone coming to work at any of our US campuses to be vaccinated," Facebook's vice president of people Lori Goler told The Verge.

Netflix will also require the casts and some crew on its productions in the US to be vaccinated against COVID-19.