Hank Azaria voices a number of different characters

'Simpsons' actor Hank Azaria has said he's "willing to step aside" over controversy about his voicing of Indian character, Apu Nahasapeemapetilon.

Speaking on The Late Show with Stephen Colbert the actor, who voices a number of different characters in the show, said he understood concerns and had been aware of them for years.

The portrayal was criticised most recently in a documentary 'The Problem with Apu' - which questioned the stereotypical depiction of Indian immigrants that Apu creates.

"I think the most important thing is to listen to Indian people and their experience with it," Azaria said. "I really want to see Indian, South Asian writers in the writers room…including how [Apu] is voiced or not voiced.

"I'm perfectly willing to step aside. It just feels like the right thing to do to me.

"It's come to my attention more and more over the past couple years," he added.

Earlier this month 'The Simpsons' writers responded to the criticism with an episode where Marge reads her favourite childhood book to her daughter Lisa.

Marge realises the story is more racist and offensive than she remembered and tries to edit it as she reads.

Lisa replies: "Something that started decades ago and was applauded and inoffensive is now politically incorrect.

"What can you do?"

A photo of Apu appears and Marge says: "Some things will be dealt with at a later date."

Lisa adds: "If at all."