In a statement issued on the second anniversary of the 26/11 attacks, Dr Singh said: "We will never succumb to the designs of our enemies. We pledge to redouble our efforts to bring the perpetrators of this crime against humanity to justice."
He added: "On this day of remembrance, we salute the courage, unity and the resolve of ordinary Mumbaikars and the brave and selfless action of our men in uniform during the attack."
"It is this spirit and strength of character of the Indian people that will defeat such forces that seek to threaten our social fabric and way of life", he said.
He said, "the nation joins the bereaved families in remembering and mourning those who perished in the barbaric attack."