The 'Hercules 3D' star denies he is dating Miley Cyrus - whom he has recently been spotted kissing in both Miami and Las Vegas - claiming they are just really good friends.
He told radio host Ryan Seacrest: "Are we dating? No. It just makes me laugh. I've been friends with Miley for six years. She's a great girl... We are friends and we run in the same circle."
Kellan, 28, also called Miley, 21, a "cool secure woman" and said he doesn't want to be in a relationship at the moment.
He added: "I'm happily single ... I'm not [looking for a relationship] right now. I'm enjoying life and traveling quite a bit ... there's no real time to find the one."
However, a source claims although Kellan and Miley are "just enjoying themselves" with their flirty behaviour, they have a "great chemistry".
The insider told E! news: "They are both spontaneous, fun people, so their personalities match. They are having fun together. They have very similar outlooks. I am not sure if it has a future but they have great chemistry so for the time being they are just having fun."