Sri Lanka's election commission declared former defense secretary Gotabaya Rajapaksa as the winner of the presidential election on Sunday.

Rajapaksa won 52.25 percent of the votes, while his main rival and government minister Sajith Premadasa received 41.99 percent, the election commission said. Premadasa has already conceded defeat.

In a statement earlier, Premadasa congratulated Rajapaksa for his victory at the polls, and said he would be stepping down as the deputy leader of the United National Party, which is the largest party in the ruling United National Front government.

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"At the conclusion of a hard fought and spirited election campaign, it is my privilege to honor the decision of the people and congratulate Mr. Gotabaya Rajapaksa on his election as the seventh President of Sri Lanka," Premadasa said in a statement.

"I express my heartfelt gratitude to all of our citizens who voted for me, in all corners of the island (country)," he added.

Premadasa said the polls conducted on Saturday was the most peaceful in history and appealed to Rajapaksa, as the new president of Sri Lanka, to strengthen and protect the the democratic institutions and values that enabled Rajapaksa's success as Sri Lanka's seventh president.

By late Sunday morning, Rajapaksa had already won 50 percent of the total votes with his party, the Sri Lanka Podujana Peramuna (SLPP) predicting his win at 53 percent, according to local media.

The Sri Lanka Elections Commission said it will announce the winner on Sunday afternoon and the new president is likely to be sworn early this week.

(Cover: President-elect Gotabaya Rajapaksa waves at his supporters as he leaves the election commission after he was been announced the new president of the country in Colombo, Sri Lanka November 17, 2019. /Reuters Photo)