French fighter jets pound Islamic State stronghold

French President Francois Hollande has made good on his promise to deliver a "merciless" response to the Paris attacks, with fighter jets launching France’s biggest raid in Syria to date on the Islamic State stronghold of Raqqa.

Footage uploaded on to an official French military Facebook page today shows scores of fighter jets taking off in darkness to attack the Syrian city, which Islamic State declared its capital in early 2014.

"The raid ... including 10 fighter jets, was launched simultaneously from the United Arab Emirates and Jordan. Twenty bombs were dropped," the French defence ministry said.

The statement said the raid was carried out alongside US forces, and struck a command centre, recruitment centre for jihadists, a munitions depot, and a terrorist training camp.

The French military conducted the raid just days after Islamic State claimed responsibility for co-ordinated attacks in Paris that have killed 132 people.

Francois Hollande had declared the attacks as "an act of war".