An opposition leader in Gabon says he will refuse a post in the president's new cabinet, contradicting a government statement.

President Ali Bongo's government announced on Friday that Jean de Dieu Moukagni Iwangou, president of a coalition that has been calling for a change in leadership after nearly 50 years of rule by the same family, would be the new minister of state for agriculture.

But Moukagni Iwangou said in a Facebook post Saturday that he would not accept the appointment. He said he would focus instead on ensuring that "inclusive dialogue" takes place before a presidential election expected next year while following French investigations into the Bongo family's assets.

Ali Bongo became president of Gabon in 2009 following the death of his father, longtime ruler Omar Bongo.