Punjab Congress chief Amarinder Singh on Saturday said India must go for limited retaliatory action against Pakistan for abetting and sponsoring the terror attack on a military base in Uri in Jammu and Kashmir, that left 18 Indian soldiers dead."While the nature and type of retaliation should be decided by the army, it must at no cost let the perpetrators of the terror attack go unpunished," he told reporters here.Amarinder Singh however stressed that though he was a strong advocate of people-to-people contact between India and Pakistan, this incident should go unavenged."Since the common man on both sides want peace and cordial relationship. that does not mean our army should let the wanton killing of our soldiers go unpunished," he said."It's the question of maintaining the morale of our army and that is non-negotiable," said Singh, who also served in the Indian Army.