A top court in the Democratic Republic of Congo has jailed an opposition politician for seven years after finding him guilty on 12 charges, including spreading false rumours and insulting the head of state.

Jean-Marc Kabund had been detained since August last year when he was arrested for criticising President Felix Tshisekedi and his government.

Mr Kabund is a former vice-president of the DR Congo parliament. He was also a close ally of President Tshisekedi until their fallout in early last year.

He went on to form the Alliance for Change political party, under which he planned to run for president in the December elections.

He will not have an opportunity for appeal as the decisions of the Court of Cassation, which sentenced him, are final and not subject to appeal.

"This is an extremely harsh decision, especially as there is no appeal," his lawyer Kadi Diko said after the Wednesday sentencing.

He told the Reuters news agency that Mr Kabund received four months each for the first nine offences and 16 months each for the last three.