Accra, Rabi'I 11, 1438, December 10, 2016, SPA -- Ghanaian President John Dramani Mahama has conceded defeat in this week's elections, congratulating his challenger Nana Akufo-Addo, dpa reported. Mahama called Akufo-Addo on Friday, said John Boadu, acting general secretary of the opponent's New Patriotic Party. The 72-year-old winner was happy and saw his win as challenge from Ghanaians to prove he can deliver, Boadu added. The electoral commission has still to announce the official election results. -- SPA 02:21 LOCAL TIME 23:21 GMT www.spa.gov.sa/w287054