The Jealous singer avoided answering a question about Kate during an interview with US radio show 94.7 FM on Tuesday.
"Okay, I have to ask you. I hope you don't get mad at me. What was going on with you and Kate Hudson this weekend?" radio host Dana McKay asked, to which Nick replied: "I'm not gonna get mad at you, but I'm also not gonna talk about it."
Nick Jonas has declined to comment on Kate Hudson dating rumours
"You don't kiss and tell?" Dana persisted.
"I keep some things to myself," Nick answered.
Speculation about Kate and Nick began when they were spotted together on several occasions over the weekend. The pair were seen giggling happily on rides at Disney World in Orlando, followed by a cosy brunch in Miami. Kate also turned up when the 23-year-old musician performed at the House of Blues in Orlando, where he sung his new single Levels.
It's not the first time the screen beauty has been seen in the audience at one of his concerts. On 9 September she joined a host of other celebrities at his gig in New York.
Kate Hudson was seen in the crowd at Nick's gig in Orlando
Nick is the first person Kate has been linked to following the end of her relationship with Muse frontman Matt Bellamy in late 2014. Nick is also single after calling time on his two year relationship with former Miss USA Olivia Culpo in June, but has since been linked to Kendall Jenner and his ex-girlfriend Selena Gomez.
While Kate enjoys herself with Nick, her ex-fiancé has also moved on with new girlfriend Elle Evans, 25. He was her plus one when her film movie coincidentally called Muse premiered at the Cannes Film Festival.
Matt has been linked to the young actress since February, but has stayed tight-lipped about their relationship. In the wake of his break up with Kate, the musician said it was for the best.
"Look. We had a great relationship, she's a lovely person, we're better off as friends," he told NME. "Definitely in the last few months I've been feeling much better. Actually, I've been feeling really good."