The Vatican on Wednesday unveiled a fundraising video centred on newly elected Pope Leo, urging the faithful to support his mission amid a serious financial crisis for the Catholic Church.

The slick one-minute video was shown on giant screens in St. Peter's Square to crowds waiting for the pope's weekly audience, and spread on social media and the internet by Vatican news outlets.

It starts with footage of the white smoke that announced Leo's election on May 8, followed by his first words as pope, "Peace be with you all", and images of cheering crowds, all accompanied by gentle piano music.

The video urges people to donate to Peter's Pence - a papal fund used to support church activities and charity work which, according to latest available records, received 48.4 million euros ($55.66 million) in donations in 2023.

The pope's home nation, the United States, accounted for the biggest share, equal to just over 28% of the total, but expenses far outstripped offerings, with the fund disbursing 103 million euros in the year, the Vatican said.

"With your donation to Peter's Pence, you offer tangible support as the Holy Father takes his first steps as Pope. Help him proclaim the Gospel to the world and extend a hand to our brothers and sisters in need," the video says.

Although the Vatican has not published a full budget report since 2022, the last set of accounts, approved in mid-2024, included an 83-million-euro ($94-million) shortfall, two knowledgeable sources told Reuters.

The shortfall in the pension fund was estimated to total around 631 million euros by the Vatican's finance czar in 2022. There has been no official update to this figure, but several insiders told Reuters they believe it has ballooned.