The two, who have been friends since the beginning of the show are rumoured to have started romancing recently.
The 46-year-old actor's representative, however, said, "We can confirm that they are not dating."
Reedus took to Twitter to mock the dating speculations by posting a photo of him and Arnold Schwarzenegger along with caption, "New couple alert."
According to a source, "They had a connection early on in the show. But the romance developed recently. They're still pretty guarded about it."
Reedus and Kinney reportedly stayed in touch through texts, appearances at fan conventions, and at the actress's music gigs, after her character Beth was killed off the show last year,