The son-in-law of Angolan President Jose Eduardo dos Santos told Reuters news agency that a Congolese court has sentenced him in absentia to one year in prison for real estate fraud.
Sindika Dokolo told Reuters that Wednesday’s verdict was politically motivated.
He has criticised the Democratic Republic of Congo President Joseph Kabila after he refused to step down from power.
President Joseph Kabila’s chief political rival, the former Governor of Katanga Moise Katumbi, was also convicted of real estate fraud last June shortly after he announced his candidacy to stand in an election to replace Mr Kabila.
Authorities have repeatedly rejected allegations that DR Congo’s justice system is targeting Mr Kabila’s opponents.
A DR Congo government spokesman told Reuters he was not aware of Mr Dokolo’s conviction while Mr Dokolo said he had previously been acquitted in the same case.