UNITED NATIONS, Dec. 10 (Xinhua) -- United Nations Secretary-General Ban Ki-moon Friday congratulated Nana Akufo-Addo on his election as president of Ghana.

In a statement issued here by his spokesman, Ban also thanked outgoing President John Dramani Mahama for his role in defusing tensions and preserving peace during the election period.

"The secretary-general congratulates the Ghanaian people, who turned out in large numbers to participate in the presidential and parliamentary elections on 7 December," the statement said. "He also commends the Electoral Commission for the successful organization of the elections."

The secretary-general reiterates the commitment of the United Nations to continue assisting the government of Ghana in consolidating democratic and development achievements, according to the statement.

Akufo-Addo, the candidate of the largest opposition New Patriotic Party Nana, has won Ghana's closely contested presidential elections, official results on Friday by the electoral commission showed.

He garnered 5,716,026 votes, or 53.85 percent of the total valid votes cast, while his closest challenger Mahama from the ruling National Democratic Congress obtained 4,713,277 votes, or 44.40 percent.