This, he added, was down to "irresponsible, unpredictable governance resulting in a continuing deterioration in social cohesion that risks leading the country into chaos".
President Ali Bongo came to power when his father Omar died in 2009.
In 2018, he suffered a stroke which sidelined him for almost a year and lead to calls for him to step aside.
A year later, Gabon foiled an attempted military coup, killing two suspected plotters and capturing seven others just hours after they took over state radio in a bid to end Bongo's rule.
Government spokesman Guy-Bertrand Mapangou announced the deaths and arrests after soldiers briefly seized the radio station and broadcast a message saying Bongo was no longer fit for office after suffering a stroke in Saudi Arabia in October.