Alicia Silverstone posed nude for a new PETA campaign against the use of leather.

The "Clueless" actress wore nothing but cowboy boots as she posed in the desert for the ad.

The PETA ad says, "Wear Vegan. Buy cactus, mushroom or apple leather instead!"

Silverstone, 46, explained why she decided to strip down for the camera.

Alicia Silverstone poses for a Peta ad

Alicia Silverstone poses nude for a PETA campaign. (PETA / Brian Bowen Smith)

JESSICA SIMPSON, ALICIA SILVERSTONE LEAD HOLLYWOOD STARS PURSUING FOUNTAIN OF YOUTH VIA NONSURGICAL PROCEDURES

"I never, ever, get naked in TV, in film, nothin', never, nope – but I've done it for PETA because that's how much it matters to me," the actress said in a press release obtained by Fox News Digital. "The amount of resources, water, food, oil for transport, the amount of energy that goes into making leather is extraordinary. It's just not sustainable. The Earth can't handle it."

PETA also released a behind the scenes video featuring an interview with Silverstone.

"If it takes me getting naked for you to care about animals then that is what I'm after," the actress said at the beginning of the video.

After explaining how leather affects the planet, she added, "My dream is to get these vegan, earth-friendly materials into the hands of famous designers. I'd rather go naked than wear animals."

The ad will be featured on a billboard in New York City's Times Square.

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This isn't the first time Silverstone has gone nude for PETA.

The "Senior Year" star posed sans clothes in 2020 for a campaign against eating meat.

Silverstone has been vegan since she was 21 years old.

Becoming vegan turned the actress into a "health nut because you feel so good, you feel so different," she explained to Self magazine in 2017.

"Being able to do something that is good for the Earth, good for the animals, and good for you all at the same time seems like such a no-brainer," she continued. "It’s like the biggest ‘Duh!'"

Silverstone has also raised her son Bear as a vegan.

Alicia Silverstone at the Oscars after party

Alicia Silverstone has been vegan since she was 21 years old. (Getty Images)

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