The winner of the Democratic Republic of Congo's historic presidential poll on Thursday hailed long-term leader Joseph Kabila as a "partner in democratic change".

Opposition candidate Felix Tshisekedi was provisionally declared elected president by the country's electoral commission in the early hours of Thursday morning.

"I pay tribute to President Joseph Kabila and today we should no longer see him as an adversary, but rather, a partner in democratic change in our country," he told a crowd of supporters at the headquarters of his UDPS party.