However, the treaty allowed France to retain strategic areas along their border with the Spanish Netherlands, including Charleroi whose fortifications were upgraded by Vauban. Now fully rehabilitated, Montal was appointed Governor, a position he retained until 1678; during the Franco-Dutch War in June 1673, he took part in the assault on the key Dutch town of Maastricht. Later the same year he repulsed an attempt by William of Orange to take Charleroi and was wounded at Seneffe in 1674. During the winter of 1676/1677, he supported a tight French blockade of the Spanish-held towns of Valenciennes and Cambrai by seizing any grain being transported from Namur and preventing reinforcements reaching either garrison.