The Biden administration will purchase 200 million more coronavirus vaccines and funnel more to states now, in a bid to deliver on the US president’s promise to curb the pandemic, a senior administration official said on Tuesday.

Biden, who took office last week, is in a race to contain the virus as faster-spreading variants threaten to increase the death toll across the United States, which has already been hard-hit.

The administration is briefing state governors on Tuesday about its plans to increase the amount of the vaccine going to those local governments to 10 million doses per week for the next three weeks, up from 8.6 million currently...