Who said "Death is the only mercy we offer."?

This quote is attributed to Dalek.

Death is the only mercy we offer. - Dalek

"Death is the only mercy we offer."

Dalek Death

"Exterminate! Exterminate!"

"You will be exterminated!"

"Daleks do not feel pity or remorse or fear."

"We are superior. We are pure."

"Death doesn't scare me anymore."

"Death and I are old friends."

"Welcome to my world."

"Death is just the beginning."