Billy Porter mixed two classic red-carpet styles while attending the 2019 Oscars at the Dolby Theatre in Los Angeles on Sunday.

The actor donned a tuxedo dress, which featured a jacket-style top and a ball gown-style skirt. He accessorized with an oversized bow tie and a statement diamond ring.

According to the Hollywood Reporter, his ensemble was designed by Christian Siriano, a fashion designer known for his gender-fluid and inclusive runway looks.

Billy Porter Oscars

Foto: Porter's tuxedo dress was designed by Christian Siriano.sourceJordan Strauss/AP

Speaking to Vogue, Porter said that he wore the dress to challenge traditional ideals of men's fashion

"My goal is to be a walking piece of political art every time I show up," Porter told Vogue. "To challenge expectations. What is masculinity? What does that mean? Women show up every day in pants, but the minute a man wears a dress, the seas part."

And while Porter said that he always wanted to wear a dress, he "just didn't know when." As a result, the actor partnered with Siriano to create a look that mixed "the masculine and the feminine."

Billy Porter attends the 2019 Oscars.

Foto: Porter told Vogue that he wore the dress to challenge stereotypes.sourceRichard Shotwell/Invision/AP

"This look was interesting because it's not drag," Porter said. "I'm not a drag queen, I'm a man in a dress. He came up with a tux on the top, and a ballgown that bursts out at the bottom."

He also said that he expected to make people uncomfortable with his attire.

"People are going to be really uncomfortable with my black ass in a ball gown," Porter said. "But it's not anybody's business but mine."

This isn't the first time Porter has mixed suits and dresses on a red carpet

While attending the American Film Institute Awards in January, the actor wore a shiny yellow dress with a matching suit jacket on top. The ensemble was designed by Calvin Klein.

On Instagram, Porter said he wore the look to honor "marginalized brothers and sisters from the LGBTQAI+ community."

Billy Porter

Foto: Porter accessorized with a leopard-print head scarf and bold glasses.sourceSteve Granitz/Getty Images

Porter also broke style barriers while attending the 2019 Golden Globe awards

He wore a gray suit encrusted with beads and embroidered with flowers, but rather than wearing a traditional suit jacket, the actor's ensemble flared out into a neon-pink cape.

Read more: The 36 most iconic Oscars red-carpet looks of all time

His look, which was designed by Randi Rahm, took more than six months to create, according to the Hollywood Reporter.

Billy Porter

Foto: Porter added flare to his look by showing off his cape on the red carpet.sourceJordan Strauss/AP

Porter also told the Hollywood Reporter that he frequently uses fashion as a way to express himself.

"I have always used clothes as a tool for self-expression and find immense pleasure in celebrating life, love and joy through fashion," Porter said.