The Congress president had congratulated Modi on May 20 hours after he was elected leader of the Bharatiya Janata Party parliamentary party and the National Democratic Alliance, thereby setting the stage for him to become prime minister.
Sonia is also the chairperson of the Congress-led United Progressive Alliance.
Rahul had led the party in the Lok Sabha polls. The Congress saw the worst debacle after remaining in office for ten years.
Image: Congress chief Sonia Gandhi with son and party Vice President Rahul
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