Just days after he attended a big rally of the Punjab Congress in Bathinda and even welcomed Amarinder Singh's appointment as the Punjab Congress president, Congress leader Sukhpal Singh Khaira on Friday joined the Aam Aadmi Party (AAP).Though the move is seen as a blow to the Congress which is trying to re-invent itself ahead of the 2017 assembly polls, the Congress and the ruling Shiromani Akali Dal dismissed Khaira's joining the AAP as a non-event.Khaira, a former Congress legislator, has been a firebrand and outspoken leader of the Congress.The Congress termed Khaira's exit "a good riddance".Punjab Congress leader Laal Singh wondered how Khaira had started seeing faults with the Congress leadership just days after hailing Amarinder Singh's appointment as the Punjab Congress president."People like Khaira can never be happy and comfortable with any political party. It is his third party having started from the Akali Dal, then joined the Congress and now he has joined the AAP," Laal Singh said, describing Khaira as an "opportunist".Punjab Chief Minister and Akali Dal chief patron Parkash Singh Badal said Khaira's joining the APP was "hardly an issue".The Akali Dal described Khaira's action as a "marriage of political frustration with political opportunism".