The actor starred as Ron, boy wizard Harry's friend, in the film adaptations of JK Rowling's books from the age of 11.
The last film – Harry Potter And The Deathly Hallows Part 2 – was unveiled in 2011 but Grint has now said he would like to revisit the character.
He was quizzed about it on This Morning, and said: "Yeah, I think if the timing was right and everyone was kind of coming back, I would revisit."
"I feel quite protective of him as well.
"It was my whole childhood.”
Grint was on the show to discuss new psychological thriller Knock At The Cabin, which sees a young girl and her parents taken hostage by four armed strangers.
The star said it combined his fears of an apocalypse and intruders.
"This does entangle both of my fears," he said. "It was quite stressful!”
Grint had to adopt a US accent for the role so worked with a coach to perfect it.
“I have done it [before] so I’m getting used to it," he said.
"You have to be conscious of what you’re doing with your tongue in your mouth when you’re talking, it’s very different… American people have a very different tongue shape in what they do with it, I don’t know! It’s very technical!”
This Morning airs weekdays from 10am on ITV1 & ITVX.
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