The CPI(M) today demanded that Prime Minister Manmohan Singh own up responsibility for the corruption scandals plaguing his government including the 2G and KG basin issues, but stopped short of asking for his resignation. "The role of Prime Minister in the scandals involving the 2G spectrum distribution and KG basin is questionable. He must own up the responsibility," CPI-M general secretary Prakash Karat told reporters at the end of the two-day party central committee meeting in Kolkata.