COURBEVOIE, France — One of Africa’s wealthiest presidents said this week that he was giving up at least some of his holdings “to the people of Gabon,” a declaration heralded by his inner circle but quickly met with skepticism by critics who pointed out the legal and political pressure the leader, Ali Ben Bongo, is facing over the vast riches acquired by his family.

The holdings of the Bongo family have long been a subject of speculation and, for much of the last decade, a subject of legal action by the French authorities as well.

Mr. Bongo’s father, Omar, ruled Gabon for more than four decades until his death in 2009, accumulating fleets of expensive cars, luxurious properties in France and overstuffed bank accounts along the way.

Critics have long denounced the disparity between the lives of the people in a country where a third live on less than $1.25 a day and the family’s sumptuous properties in Paris and elsewhere in France, the focus of a long-running judicial inquiry.