What do you think? Leave a respectful comment.

WATCH: White House press secretary Jen Psaki gives news briefing with Dr. Anthony Fauci

WASHINGTON — Dr. Anthony Fauci is back in the White House briefing room.

Watch Psaki’s remarks in the player above.

Fauci, the nation’s leading infectious disease expert, was tasked by President Joe Biden to give an update on the coronavirus pandemic after largely being sidelined in recent months by former president Donald Trump.

Fauci said the new administration would “be completely open and honest” in dealing with the pandemic and, in an implicit rebuke to the Trump administration, said everything now would be “based on science and evidence.”

He also said in the Biden administration, the rule would be “if you don’t know the answer, don’t guess.”

Fauci, who repeatedly attacked by Trump for breaking with his rosy view of the pandemic, provided an update on the new, more contagious strains of the virus, which has now claimed the lives of more than 400,000 Americans.