UN Secretary-General Antonio Guterres. (File Photo: CGTN)

UN Secretary-General Antonio Guterres urged all stakeholders in DR Congo to avoid violence after the opposition candidate was declared the winner of the presidential election in an announcement contested by his rival.

"The secretary-general calls on all stakeholders to refrain from violence and to channel any eventual electoral disputes through the established institutional mechanisms in line with the Democratic Republic of the Congo's Constitution and relevant electoral laws," UN spokesman Stephane Dujarric said late Wednesday in New York.

Felix Tshiseked, the candidate of the Union for Democracy and Social Progress (UDPS), earlier Thursday was declared to have won the election by the Democratic Republic of Congo's electoral commission, signaling the first democratic transfer of power since the country's independence from Belgium in 1960.

The result was denounced by Martin Fayulu of the "Lamuka" coalition as an "electoral coup" in an interview with Radio France International.

The final results will be proclaimed in the coming days according to a new timetable after confirmation of these provisional results by the Constitutional Court in accordance with the DRC's national law.