US President Joe Biden has said his administration is mulling a mandate that necessitates all federal workers to be vaccinated against Covid-19, escalating the push for vaccination amid the rampant spread of the Delta variant and still-high vaccine hesitancy rates in parts of the country. Biden's remarks came against the backdrop of waning vaccination rates in the country despite wide availability of the shots, and as the spread of the more transmissible Delta variant caused a worrisome uptick in caseloads. The Department of Veterans Affairs on Monday announced mandatory vaccination requirements for its healthcare workers, making it the first federal agency to impose such an order. There are some 4 million employees in total in the executive branch of the federal government, including civilian workers, men and women in uniform, as well as Postal Service personnel, according to government estimates updated in June. It's not yet clear whether the federal vaccine mandate being discussed will apply to members of the military. The Centers for Disease Control and Prevention (CDC), meanwhile, updated its mask guidance Tuesday, now asking fully vaccinated people and kids to wear masks indoors in places with high COVID-19 transmission rates. UNESCO names Harappan city of Dholavira as world heritage site 300-foot-high sandstorm over this city in northwest China, video goes viral Govt won't appeal A-bomb 'black rain' ruling: says Japan PM Suga