Gov. Gavin Newsom Cornered by Wildfire Victim ... 'Why Isn't the President Taking Your Call?!?'

CA Gov. Gavin Newsom tried to use President Biden as a shield when a distraught wildfire victim confronted him Thursday -- but his efforts kinda blew up in his face.

The woman, a lawyer named Rachel Darvish, ran up to Newsom as he was getting into his car -- leaving a devastated Pacific Palisades -- and started hammering him with questions about everything that went wrong for firefighters ... and a Sky News camera crew captured the intense showdown.

Darvish demanded answers about why there was no water pressure in fire hydrants to help firefighters knock down the flames -- Newsom quickly responded by holding up his phone and telling her he was talking to President Biden at that very moment about getting aid to victims.

Perhaps he thought she'd back off when he said that, but it only made her demand more answers -- and, in fact, she asked to speak to Biden. Newsom finally had to admit, "I'm sorry. I've tried 5 times, that's why I'm walking around to make the call."

Newsom suggested he wasn't able to get a signal, but Darvish pinned him down, saying ... "Why isn't the President taking your call?"

Watch their exchange ... it only got more awkward after that.

Darvish has been extremely critical of Gov. Newsom and L.A. Mayor Karen Bass ... accusing both of being caught flat-footed and not preparing for the worst ahead of this week's hurricane-force Santa Ana winds, which fueled the firestorm.

She told Fox News, "There should have been some forethought. People were getting out of their cars to run away from the fires."

It's also clear she wasn't buying Newsom's claim about getting President Biden on the phone, and she continued peppering him with questions about water dripping nearby ... suggesting it would have made the difference when the fire was raging.