BANGUI: Opposition figures in the Central African Republic on Tuesday lashed the outcome of presidential elections that saw President Faustin Archange Touadera returned to office in disputed conditions.

The country's electoral authority, the ANE, late Monday declared Touadera winner of the December 27 vote with 53.92 percent of the ballot -- a figure that, if confirmed by the CAR's top court, means a runoff will not be needed.

The agency put the first round's turnout at 76.31 percent, although the figure accounts for only 910,000 eligible voters in a registered electorate of 1.8 million.

Two-thirds of the country is controlled by armed groups, and many voters in these areas were unable to cast their ballots.

The ANE "has taken the step of most disdainfully ignoring 947,452 Central Africans who were prevented from voting by the violence of armed groups," said runner-up Anicet Georges Dologuele, a former prime minister credited with 21.01 percent.

As a result, "51 percent of the electorate" was unable to vote, he noted in a statement that announced he would file a complaint to the Constitutional Court.

Third-placed candidate Martin Ziguele said, "I give no substance to these results, it's a masquerade, a shame for our country."

According to official figures, voting did not take place at all in 29 of 71 sub-prefecture districts and was curtailed in six others.

In almost half of the polling stations, "voting did not take place or ballot sheets were destroyed," the ANE's rapporteur, Theophile Momokoama, told AFP.

The Constitutional Court has until January 19 to validate the result. The opposition has already said it will file a suit.

The elections are seen as a key test of stability in one of the world's poorest and most violence-prone countries.

The landlocked former French colony remains in the aftershock of a civil war in 2013 that followed the ouster of Touadera's predecessor, Francois Bozize.

Thousands of people have died and nearly a quarter of the population have been displaced.

On Monday, the CAR's public prosecutor said an investigation had been launched into Bozize, whom the government accused of plotting a coup in the runup to polling day.

Government spokesman Ange-Maxime Kazagui on Tuesday said the elections had been "credible".

"The results have been announced and I can only express my joy, like all those who support... President" Touadera, he said. "It's a vote to reject violence."

Four international organisations that provided millions in funds to organise the elections praised "the resolve of Central Africans to exercise their right to vote despite the many obstacles."

The joint statement "noting the provisional results" was issued by the African Union, European Union, the United Nations and the Economic Community of Central African States (ECCAS), an 11-nation bloc that includes the CAR.

Thierry Vircoulon, a CAR specialist at the French Institute of International Relations think tank, said "this election is a giant step backward compared with 2016," the first post-war elections which were won by Touadera.

The vote is "anything but credible", he said in an interview with AFP.

"Real turnout" was 30 percent, he said, pointing to alleged irregularities that had taken place before the outcome was unveiled.

A coalition of political opposition groups had called on December 19 for the elections to be cancelled, and reiterated that appeal three days after the vote.

Elections were also held on December 27 for the CAR's legislature, whose results have yet to be announced.