Daniel Radcliffe can understand why people are "frustrated" with Johnny Depp's casting in the 'Fantastic Beasts' franchise.

Daniel Radcliffe

Daniel Radcliffe

The 'Harry Potter' actor admits it is "very hard" for him to comment on the decision to keep the 54-year-old star in his role as Gellert Grindelwald despite a backlash from fans over his controversial divorce from Amber Heard, in which she claimed he'd been abusive towards her throughout their marriage before later dropping the allegations, because producers gave him a "great start".

And Daniel drew reference to Jamie Waylett, who played bully Vincent Crabbe but was dropped from the final two 'Harry Potter' films for being arrested for growing marijuana plants in 2009.

He told Entertainment Weekly: "It's a very hard thing for me... I can see why people are frustrated with the response that they were given from that ... I'm not saying anything that anybody hasn't already said -- and this is a weird analogy to draw -- [but] in the NFL, there are lots of players arrested for smoking weed and there is other people's behaviour that goes way beyond that and it's tolerated because they're very famous players.

"I suppose the thing I was struck by was, we did have a guy who was reprimanded for weed on the [original 'Potter'] film, essentially, so obviously what Johnny has been accused of is much greater than that."

Author J.K. Rowling, who is responsible for both the 'Harry Potter' and 'Fantastic Beasts' franchise, previously admitted producers had considered recasting Johnny's role in 'Fantastic Beasts: The Crimes of Grindelwald' but decided against it once abuse allegations were dropped.

Taking to her website, she wrote: "When Johnny Depp was cast as Grindelwald, I thought he'd be wonderful in the role. However, around the time of filming his cameo in the first movie, stories had appeared in the press that deeply concerned me and everyone most closely involved in the franchise.

"'Harry Potter' fans had legitimate questions and concerns about our choice to continue with Johnny Depp in the role.

"As David Yates, long-time 'Harry Potter' director, has already said, we naturally considered the possibility of recasting. I understand why some have been confused and angry about why that didn't happen.

"However, the agreements that have been put in place to protect the privacy of two people, both of whom have expressed a desire to get on with their lives, must be respected.

"Based on our understanding of the circumstances, the filmmakers and I are not only comfortable sticking with our original casting, but genuinely happy to have Johnny playing a major character in the movies.

"I accept that there will be those who are not satisfied with our choice of actor in the title role. However, conscience isn't governable by committee. Within the fictional world and outside it, we all have to do what we believe to be the right thing."