Zimbabwean opposition official Tendai Biti arrives at the magistrate's courts in Harare following his deportation from Zambia in August 2018. File picture: Tsvangirayi Mukwazhi/AP

Harare, Zimbabwe - A Zimbabwean court has convicted prominent opposition politician Tendai Biti for announcing that his party's leader won disputed elections held in July.

Biti was on trial for "unofficial and false declaration of results." Magistrate Gloria Takundwa fined him $200 for the offence.

Biti, also a leading human rights lawyer, fled the country to neighbouring Zambia in August citing threats to his life. He was deported back to Zimbabwe days later and arrested for allegedly violating the electoral law.

Main opposition leader Nelson Chamisa and his party, the Movement for Democratic Change, have rejected the election results, claiming the electoral agency rigged the vote to ensure a win for President Emmerson Mnangagwa.

Zimbabwe has sunk deeper into political turmoil and economic decline since the elections, the first to be held without former longtime ruler Robert Mugabe. At one time the elections were viewed by both local and the international community as key to turning the country around after decades of repression.