President Emmerson Mnangagwa on Sunday called Zimbabwe a "mature democracy" after winning a second term in office despite the opposition rejecting the result of a vote that international observers said fell short of democratic standards.

"We have demonstrated that we are a mature democracy," the president said, praising a high turnout. "We take pride in the fact that we are an independent and sovereign nation."

Zimbabweans voted Wednesday and Thursday for president and parliament in polling marred by delays that sparked opposition accusations of rigging and voter suppression.

A spokesman for Chamisa's Citizens Coalition for Change (CCC), Promise Mkwananzi, said the party did not sign the final tally, which he described as "false". "We cannot accept the results," he told reporters, saying the party would soon announce its next move.

Mnangagwa, won 52.6 percent of the ballots against 44 percent for his main challenger, Nelson Chamisa, 45, according to official results announced late Saturday by the Zimbabwe Electoral Commission (ZEC).

The vote has been watched across southern Africa as a test of support for Mnangagwa's ZANU-PF party, whose 43-year rule has been accompanied by a moribund economy and charges of authoritarianism.

Foreign monitors announced Friday that the elections had failed to conform to regional and international standards.