She wasn't old enough to vote for him, but pop star Olivia Rodrigo has lent US President Joe Biden a hand, working to promote Covid-19 vaccines.

The singer, 18, met Mr Biden, 78, and national virus chief Dr Anthony Fauci, 80, to film an advert aimed at encouraging young people to get jabs.

The White House is turning to Rodrigo and her massive fan following for help. The singer behind hits like "Driver's Licence" and "Deja Vu" is expected to share the educational videos filmed on Wednesday with her 28m social media followers. The White House will also promote them.

Olivia Rodrigo is at the White House today to meet with President Biden and Dr. Fauci and discuss the importance of young Americans getting vaccinated. pic.twitter.com/s95KtOkrsF

? The White House (@WhiteHouse) July 14, 2021

Speaking from the White House briefing room, Rodrigo said she was "honoured and humbled" to spread the important message of youth vaccination.

Rodrigo's guest appearance is the latest effort by the Biden administration to enlist celebrities in the vaccine drive. Country singer Brad Paisley and actor Jennifer Garner were among those previously tapped for the cause.

After an initial surge in vaccinations across the US, rates have plateaued in recent weeks, amid an alarming increase in Covid-19 case rates.

Mr Biden had set a goal of getting 70% of US adults at least one dose by the 4 July holiday, but missed that mark due in part to hesitancy among Americans of Rodrigo's generation.

Overall, about 67% of Americans 18 and older have received at least one shot.

Cooper Lawrence, a journalist and author of Celebritocracy, said she thinks Rodrigo's efforts may result in a vaccination bump among her peers.

"Research shows that people assume celebrities have insider information that we don't have," she said. And celebrity's tend to hold the greatest sway over young people, meaning Rodrigo is the perfect person to relay this message.

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