BJP leader Ravneet Singh Bittu reacted to Congress chief Mallikarjun Kharge's letter to PM Narendra Modi asking him to "discipline" BJP leaders. "Kharge should teach his 'Pappu' first," said Bittu. "They made him LoP but he's still a 'Pappu'," he added. Bittu had earlier called Rahul Gandhi "terrorist number one" over his remarks in US.