"Congratulations to @OfficeOfRG on being elected as Congress President unopposed. Wish you a sterling tenure in the footsteps of the illustrious past presidents of the more than a century-old Congress party," he said in a tweet tagging Gandhi's official Twitter handle.
Earlier, Congress' Central Election Authority head Muallapally Ramachandran had said Mr Gandhi was elected unopposed as the Congress president.
47-year-old Mr Gandhi succeeds his mother Sonia Gandhi, who held the post for 19 years.
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