Joe Biden pledges to distribute 100m vaccine shots in first 100 days of presidency – as it happened

• President-elect reiterates call for Americans to wear masks
• Trump campaign official reportedly tests positive days after staff party
• FDA analysis of Pfizer vaccine raises no safety concerns
• Texas attorney general suing four states over election results
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12.54am GMT

Here's a recap, from me, Joan E Greve and Sam Levine:

12.42am GMT

In Arizona, the state's Supreme Court rejected yet another Republican challenge to the election:

BREAKING:

The Supreme Court of Arizona REJECTS Republicans' election contest.

"IT IS ORDERED affirming the trial court decision and confirming the election of the Biden Electors." cc: @LawCrimeNews pic.twitter.com/7gCtMLajxI

Related: The US election's 'safe harbor' deadline is here. What does that mean for Biden?