Guinea's government has suspended all street protests in what it says is a move to prevent the spread of the coronavirus.
The opposition politician who lost last month's presidential election, Cellou Dalein Diallo, had called for mass protests this Wednesday.
He failed in his bid to get the result overturned in the courts after alleging that the vote had been rigged.
Guinea has been through a period of political instability since the 82-year-old president, Alpha Condé, changed the constitution to run for a third term.
Dozens of people have been killed in political violence in recent months.