Franck Diongo, leader of the minor opposition MLP party, has been sentenced to five years in prison on Wednesday (28 December) by a court in Democratic Republic of Congo. He was found guilty of illegally detaining three soldiers during a protest last week in the capital Kinshasa, a human rights advocate said.

Diongo, who is also a member of the main coalition group Le Rassemblement, was arrested on 19 December, the day when Joseph Kabila was supposed to step down as president after his mandate expired.

Diongo's arrest and subsequent sentencing is said to have come at a time when the Central African country is embroiled in political crisis with respect to holding the presidential election. The judgement might jeopardise the talks among different opposition parties meant to organise the election next year.

Diongo could not defend himself in the court due to his failing health, Georges Kapiamba, a lawyer and human rights advocate who attended the trial, told Reuters. The opposition MP called the decision "totally political", while the government denied that the prosecution is politically motivated.

The politician alleged that he was mistreated by authorities reportedly dressed in civilian clothes, who assaulted him. Diongo, MP for Lukunga, said he had to call for help as the presidential guards surrounded him, and the UN peacekeeping mission, Monusco intervened. However after the UN forces left, the minister and his guards were arrested.

The ruling comes at a time when Kabila's ruling coalition party representatives and Congo's main opposition bloc said they are close to reaching a consensus that the president would step down by the end of 2017 after his successor is elected.

Prosecution against Diongo and other opposition leaders could hamper the negotiations, Felix Tshisekedi, the leader of the opposition delegation at the talks, said on Wednesday (28 December).

"We go from one provocation to the next," Reuters cited Tshisekedi as saying. "If this continues, we won't be able to sign an accord."

The main opposition bloc has demanded that one of its members be named as prime minister. They also want the country's electoral commission be reconstituted.

Kabila faces severe criticism from his opponents of clinging to power, which he denies. The election was supposed to take place in November 2016 but it is now not expected to happen until at least April 2018. The government cited delays in registering millions of voters for postponing the elections.

DRC anti-Kabila protests
Residents chant slogans against Joseph Kabila as personnel from the UN's peacekeeping force, Monusco, patrol during demonstrations in the streets of the capital, Kinshasa on 20 December 2016 Thomas Mukoya/Reuters