I won't dignify evil IS terrorist: PM

Tony Abbott says using different label to "death cult" to describe Islamic State militants would dignify the movement.

Tony Abbott says he won't dignify Islamic State militants by using the terror group's own name. (AAP)

Prime Minister Tony Abbott has defended branding Islamic State a death cult, saying he won't dignify terrorists by using their own name.

Some Islamic leaders have warned the label could be promoting propaganda from the militant group.

"I am never going to dignify this evil movement by calling it what it claims to be," Mr Abbott told Radio 3AW on Friday.