The US-led coalition has killed a key leader of the Islamic State (IS) militant group in Syria, the Pentagon said on Saturday.

"Coalition warplanes targeted and killed Tunisian Boubaker al-Hakim, in Raqqa, Syria, November 26," Pentagon spokesman Ben Sakrisson said in a statement emailed to AFP. "Al-Hakim was an ISIL leader and longtime terrorist with deep ties to French and Tunisian Jihadist elements."