Opposition parties in the volatile Central African Republic on Tuesday stood by their rejection of President Faustin Archange Touadera's re-election, a day after his victory was confirmed by the country's top court.

In a statement, a coalition of 15 parties called COD-2020 said it "does not recognise" the outcome.

It argued that Touadera was backed by just 17 percent of registered voters and the ballot was marred by "innumerable frauds and irregularities."

The elections "are just a masquerade and in no way reflect the will of the Central African people," the statement said.

On Monday, the Constitutional Court declared Touadera re-elected with 53.16 percent in the first round of voting on December 27.

However, the official turnout was just 35.25 percent, reflecting intimidation from armed groups which control two-thirds of the country.

The runner-up was former prime minister Anicet Georges Dologuele, with 21.69 percent.

Touadera, a technocrat whose background is in mathematics, was first elected in 2016 after a civil war that left thousands dead and drove hundreds of thousands from their homes.

His shaky government depends on support from a large UN peacekeeping force and military backing from Russia and Rwanda.

The December 27 vote was preceded by an attempt by a newly created coalition of militias to advance on the capital Bangui.

Touadera said the operation, which was thwarted, was the brainchild of his predecessor, Francois Bozize, a charge Bozize denies.

Thirteen of Touadera's 16 electoral rivals had filed a suit to the Constitutional Court over the provisional results.

They argued that his victory was the result of "massive fraud" and insecurity.

The judges annulled or amended results from certain polling stations because of irregularities, but said the small numbers of votes involved "could not have affected" the overall outcome.

They dismissed several other complaints on the grounds that the plaintiffs had failed to provide "irrefutable evidence" to back their claims.

Its ruling, said COD-2020, was "based on political motivations" and ignored evidence that had been brought forward.

Landlocked and mired in poverty despite its wealth in diamonds and other minerals, the CAR has experienced negligible peace since gaining independence from France in 1960.

The 2013 civil war was sparked by the overthrow of Bozize, who himself had seized power a decade earlier.

Clashes since 2013, often along sectarian or ethnic lines, have caused thousands of deaths and displaced nearly a quarter of the population.

The UN says 2.8 million people will need humanitarian aid and protection this year.

The coronavirus pandemic, meanwhile, has had a devastating impact on an economy already rated second poorest in the world by the UN's Human Development Index.

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