The African Court on Human and Peoples' Rights has asked Benin not to impose a controversial 20-year jail sentence on opposition politician Sebastien Ajavon for a drugs conviction, his lawyer told AFP on Saturday.
Ajavon is known as Benin's "chicken king" because he made his money in livestock.
The former presidential candidate, who stood against eventual winner Patrice Talon in 2016, was convicted at a special tribunal in Porto-Novo in October.
An international arrest warrant was issued as he was not present at the hearing, which his Paris-based legal team denounced as having "serious irregularities".
No appeal is possible at the economic and terrorism tribunal (CRIET) but Ajavon's lawyers took the case to the African court, which ordered Benin to "suspend the execution of the judgement" pending further consideration.
"The African Court on Human and Peoples' Rights has given a total vote of no confidence in the state of Benin by ordering it to immediately suspend the implementation of the decision of the CRIET which found Sebastien Ajavon guilty," said lawyer Julien Bensimhon.
"It is recognition of the illegal and undemocratic nature of the way in which the CRIET was created and functions, which we have already denounced," he added.
Bensimhon said he hoped the Benin authorities would comply with the court's request, which was made on Friday.
Despite backing millionaire businessman Talon to help him win the presidency, relations between the two men have since soured.
Talon's political opponents have accused him of leading a crackdown.
Ajavon in particular has faced a slew of legal action, including the drugs charges, which relate to the discovery of 18 kilogrammes cocaine in a container destined for one of his businesses.
He previously went to the African court in Arusha, Tanzania, to demand nearly $990 million in damages from Benin on the grounds that he had been subjected to "harassment" and a "calculated plot" for two years.
Ajavon has made no secret of his desire to run again for the presidency and in March founded his own political party, the Social Liberal Union (USL).
There was no immediate reaction from the government to the African court's ruling.
But Ajavon's political allies were expected to meet on Saturday evening to discuss its implications.
"We prefer not to comment for the moment," said one senior USL member.