The actor was responding to a question about his friendships with his Potter co-stars, while conducting press interviews for his new movie The Woman in Black, when he revealed he and Grint "never text each other, we never see each other" - but he states when they do get together, they're the best of friends.
Clearing up his remarks during an appearance on Los Angeles DJ Ryan Seacrest's radio show on Tuesday, Radcliffe said, "We have never texted each other in 10 years of filming... We are lazy texters... and we both know that's how the other person is.
"But I know that the next time I see Rupert we will sit down next to each other and chat and it'll be like old times. It'll be fantastic."
And the young Brit apologised to fans who feared their film heroes had fallen out in real-life.
He added, "If any fans heard that and got upset or it was distressing... me and Rupert are very, very good friends; it's just that we're not constantly texting each other."