THE HAGUE, Netherlands — Appeals judges at the International Criminal Court have upheld most of the convictions of a former Congolese vice president for interfering with witnesses during his war crimes trial, and ordered the original trial chamber to review his sentence.

Jean-Pierre Bemba was sentenced last year to a year in prison and fined 300,000 euros for interfering with witnesses in his war crimes and crimes against humanity trial at the court.

The sentence came on top of an 18-year prison term he is serving for crimes committed in Central African Republic by a militia he commanded.

Sending the case back to trial judges, the appeals chamber said Thursday that the trial chamber wrongly assessed the gravity of the offenses.

Convictions also were largely upheld against four members of Bemba’s legal team.