An appeals court in Senegal has handed down a six-month suspended prison sentence to the country’s main opposition leader, Ousmane Sonko, in a defamation case brought against him by a government minister. The court decision bars Sonko from running in the next year’s presidential election, which means that President Macky Sall’s most prominent political rival will be unable to challenge him for the presidency. However, the case can still be appealed. Judge Mamadou Cissé ordered Sonko to pay 200 million West African francs ($336,000) in damages and interest relating to the case. If he fails to pay the fine, he could face imprisonment.

Senegal’s public prosecutor had asked for a two-year sentence for “forgery, use of forgery, defamation, and insults,” in the suit brought by Tourism Minister Mame Mbaye Niang. Sonko, who is a popular opposition figure, did not show up to court on Monday. In a statement issued the day before, he announced that he would no longer respond to court summons.

Sonko had earlier been handed down a two-month suspended prison sentence and ordered to pay damages by a lower court in March. During the previous stages of the trial, there had been protests by Sonko’s supporters. Given the longstanding feud between Sonko and the government, there was a heavy security presence in Dakar on Monday.

This case marks a significant sporting point in the run-up to the election, as Sonko has been seen as a serious contender for the presidency. It is likely that the opposition party will continue to push back against the government given the animosity between them. The continued imprisonment of Sonko, or any form of injustice, may trigger further clashes with the security forces. It remains to be seen how the events of Monday play out and what consequences they will have on the political landscape of the country.