The former Jonas Brothers star was polite but firm when he told US radio station 94.7 Fresh FM that he did not want to talk about his private life.
When asked what was happening with Kate, he replied: "I'm not gonna get mad at you but I'm also not gonna talk about it. I keep some things to myself."
He was more forthcoming when asked about how he feels about dating speculation in general, saying: "I don't know – I'm still trying to figure that out myself. The internet's a strange place where one little thing can turn into a lot, but it's about how much of that you kind of want in your world and just living your life and knowing that people will have their opinion but it's not to be concerned with."
Nick, 23, was pictured with Kate, 36, having lunch at Disney World in Florida over the weekend and riding a rollercoaster, leading to inevitable hook up rumours. People magazine has pointed out Nick appears in new TV series Scream Queens with Kate's brother Oliver.
Musician Nick split from girlfriend Olivia Culpo in June after a two-year relationship, while Kate ended her engagement to Muse's Matt Bellamy last August. They have a son together, Bing. Kate also has a son, Ryder, from her marriage to rock star Chris Robinson.
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