An environmental group has challenged Pope Francis to “go vegan” for Lent in exchange for $1 million dollars to go to a charity of his choice.

An organization called Million Dollar Vegan, supported by celebrities including Paul McCartney, Woody Harrelson and Mena Suvari, launched a video announcing its challenge to the pontiff and enlisted a 12-year-old animal rights activist named Genesis Butler to write an open letter to the pope.

“We’re asking Pope Francis to go vegan for Lent. The million-dollar vegan campaign launched on February 6 in 15 countries around the world supported by an incredible coalition of activists, researchers, and celebrities,” the video begins.

The group says it is appealing to Pope Francis, who has made care for the environment a hallmark of his pontificate, to protect the planet “by drawing attention to the devastating impact of animal agriculture.”

“If he agrees to go plant-based we will give one million dollars to the charity of his choice,” it says.

“By going plant-based for Lent, he will be leading the way to a more sustainable planet,” the video declares, before its final appeal: “Join us and fight climate change with diet change.”

Although Francis has campaigned for “profound changes in lifestyles, models of production and consumption” for the sake of the planet, going vegan could prove a bridge too far for the meat-loving pope.

The pontiff’s native Argentina is the sixth-largest producer of beef in the world, outranking Japan, Canada, Australia, Russia, and Mexico. According to a 2016 Guardian article, the pope’s favorite meal consists of steak, empanadas, and ice-cream.

Roman Catholics abstain from eating meat on Fridays during Lent, the 40-day period that begins on Ash Wednesday and ends with Holy Week and the commemoration of Jesus’s passion, death, and resurrection on Easter Sunday.

Million Dollar Vegan is appealing to the pope to lend his moral voice to their cause.

“The current eating habits of predominantly richer nations are causing global destruction and devastation,” Ms. Butler claims in her letter. “Animal farming uses 83 percent of agricultural land but yields just 18 percent of our calories.”

“With 815 million people suffering from malnutrition, imagine how many hungry people we could feed across the world if we moved away from such wasteful foods,” she writes.

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