The 47-year-old Rahul will formally assume charge as the 62nd president of the country’s oldest political party on December 16, two days before the results of the Assembly elections to Gujarat and Himachal Pradesh, that could set the tone of the Lok Sabha elections of 2019.

The announcement was made by Mullapally Ramachandran, the chairman of the Central Election Authority (CEA), at a packed press conference at the AICC headquarters which sparked off instant celebrations, distribution of sweets and bursting of crackers.

"Since the withdrawal date and time is over and as there is only one candidate, as per Article XVIII(d) of the Constitution of Indian National Congress, I hereby declare Rahul Gandhi elected as president of the Indian National Congress," said Ramachandran, flanked by Madhusudan Mistry and Bhubaneshwar Kalita , the other members of the CEA.

Rahul was campaigning in Gujarat when the announcement was made and Ramachandran said that the certificate of election would be handed over to the president-elect ceremonially on Saturday.

Central and state-level leaders of the Congress have been asked to remain present at the AICC when Rahul would formally take charge at the party president. The new role of outgoing president Sonia Gandhi is yet to be spelt out, but Congress leaders said the party would continue to benefit by her "wise counsel".

The immediate task before Rahul would be to announce his team and appoint presidents of various state units of the Congress. Rahul has already declared that he would not ease out the old guard strike a fine balance of experience and youthful energy.

The change of guard also marks a generational shift in the Congress with Rahul becoming the sixth person from the Nehru-Gandhi family to helm the party.

"We will march forward under Rahul’s leadership.We also hope to build on the Gujarat results and in 2019 return to power under Rahul’s leadership," Motilal Vora, the octogenarian treasurer of the Congress, told reporters.

"This is a beginning of a new era in the Congress. Rahul Gandhi will take us away from the fractured path of the Modi and BJP," Gaurav Gogoi, who is expected to play a key role in team Rahul, said.

Prime Minister Narendra Modi also sent his greetings to Rahul on his election. "I congratulate Rahulji on his election as Congress president. My best wishes for a fruitful tenure," Modi said on Twitter.

NCP supremo Sharad Pawar, Samajwadi Party chief Akhilesh Yadav, RJD leader Tejashwi Yadav, National Conference leader Omar Abdullah were among other opposition leaders who wished Rahul on his election as Congress president.