Maksim Chmerkovskiy Dodges Questions About Whether He's Dating Jennifer Lopez

Maksim Chmerkovskiy fueled romance rumors with Jennifer Lopez when he showed up at her 45th birthday bash in Southampton, New York, on Thursday.

Whether they are just "friends," as sources have described them - or more - remains a mystery for now. The Dancing with the Stars pro sidestepped questions about the pop star before heading onstage for his July 26 performance of Sway: A Dance Trilogy in nearby Westbury, New York.

Asked if the "First Love" singer was coming to see him in the show, Chmerkovskiy, 34, told PEOPLE, "I have a lot of friends and a lot of them are coming tonight." (Lopez, 45, did not come.)

Are he and Lopez dating?

"I'm just focused on dancing," he replied. "I'm not interested in talking about anything other than the show."

For the performance, Chmerkovskiy joined his DWTS costars Peta Murgatroyd, Tony Dovolani and Elena Grinenko onstage, along with his brother Valentin and his former partner, Disney Channel actress Zendaya, and staff members from their Dance With Me Studios.

"What makes this show special for us is that except for Elena, Peta and Zendaya - everybody is a Dance With Me Studios staff member," Chmerkovskiy said.

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