Ahead of attending Narendra Modi's swearing in as Prime Minister, Congress President Rahul Gandhi on Thursday called on former Prime Minister Manmohan Singh at his residence here.Gandhi's meeting came after Nationalist Congress Party (NCP) chief Sharad Pawar and Karnataka Chief Minister and Janata Dal-S leader H.D. Kumaraswamy called on the Congress leader asking him not to quit as party President following its debacle in the Lok Sabha elections.According to party sources, several Congress leaders had met Manmohan Singh in the last few days after Rahul Gandhi offered to step down from the post.Later in the day, Rahul Gandhi, United Progressive Alliance Chairperson Sonia Gandhi and Manmohan Singh are expected to attend Modi's swearing in ceremony.