Joaquin Phoenix is engaged to his yoga instructor

One of Hollywood’s most mysterious and private stars, Joaquin Phoenix, is engaged. The quirky actor announced the happy news during a surprise appearance on the Late Show with David Letterman this week.

Fans were shocked and delighted when Joaquin, 40, demonstrated a particularly challenging yoga move on the floor of Letterman’s studio in the middle of his segment – a move which he claimed he had learned from his “gargantuan,” six-foot-two yoga instructor.

"This is the crazy part of the story," the actor said afterwards. "We started dating, and I think she's the one. I proposed to her and she said yes."

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Even David seemed stunned by the announcement. “You proposed to her? So you’re getting married?” he asked in disbelief.

“Well yeah, if everything works out!” Joaquin replied.

Joaquin previously dated Liv Tyler in the '90s. Photo © Getty.

This will be the first walk down the aisle for the Oscar nominee, who once dated Liv Tyler in the 1990s. Most recently, the actor was in a relationship with 20-year-old DJ Allie Tilz.

Joaquin’s personal life last made headlines in 2008, when he announced his retirement from acting. A few months later, he made a bizarre, dishevelled appeared on David Letterman’s show, where he acted incoherently and was unresponsive to the host's questions. He later revealed that his "retirement" and eccentric behaviour were all part of the 2010 meta-mockumentary, I'm Still Here.

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