The 57-year-old jokingly laid back on the stage after the exchange, dramatically raising one arm up as the crowd laughed.
“Did you say Nicole Richie?” he quipped, eliciting more cackles from fans. “How are you, Nicole Richie? You have a twin.”
The coincidence was a rare acknowledgement of the Grammy winner’s high-profile separation from Kidman, which has reportedly left Urban “embarrassed to show his face on a red carpet”, the Daily Mail reported.
Their surprise split was confirmed on September 29, with reports the Practical Magic star had filed for divorce breaking the next day.
A source told People Kidman “didn’t want” to separate and had “been fighting to save” her 19-year marriage, but has been leaning on her family amidst their break-up.
The former couple share two daughters, Sunday Rose Kidman Urban, 17, and Faith Margaret Kidman Urban, 14, who Kidman stepped out with to attend the Chanel show during Paris Fashion Week.
It followed an October 7 interview with Harper’s Bazaar where she seemed to allude to the difficulties in her personal life.
“There’s something to knowing that no matter how painful, or how difficult, or how devastating something is, there is a way through,” she said.
“You’re going to have to feel it. You’re not going to be able to numb it.”