French President Emmanuel Macron begins a four-day tour of Central Africa in Gabon on Wednesday.
The exercise promises to be tricky in Libreville.
The opposition accuses the French president of "softening" through his visit President Ali Bongo, elected under controversial conditions in 2016 and likely candidate for re-election this year.
The latter will welcome him to the presidency on Wednesday evening for a dinner, followed by a sequence on Thursday as part of the One Forest Summit on the preservation of tropical forests.