The French army has stepped up its bombing campaign against the Islamic State group's oil infrastructure with two new strikes in eastern Syria, Defence Minister Jean-Yves Le Drian said Tuesday.

"We struck again twice last night in the Deir Ezzor region, (targeting) part of an oil distribution station and secondly a gas separation plant," Le Drian told journalists on the sidelines of a forum on African peace and security in Dakar, Senegal.