A letter by the interior minister to the leader of opposition Gabonese Patriotic Front justified the ban, noting the defence agreements Gabon has signed with France.

It said the protests would jeopardise the "excellent relationship" between the two countries.

The Gabonese Patriotic Front had planned a "peaceful march" on Tuesday starting from the French military base in Gabon's capital Libreville.

The party leader, Gerard Ella Nguema, told the BBC that he was going to appeal to the constitutional court against the decision, which he described as unconstitutional.

The ban on protests comes amid an anti-French sentiment in West Africa.

Earlier this month, five opposition leaders were arrested following such a demonstration in the Chadian capital N'Djamena.

Gabon hosts French forces, whose missions are focused on training African troops and French soldiers in tropical zones.