PARIS — France conducted a further airstrike against bases of the Islamic State forces, destroying another two bases at Raqqa in Syria, the defense ministry said Tuesday.

"The Chammal mission destroyed two operational bases of terrorist fighters," the ministry said.

The mission followed two airstrikes flown on Sunday night as France responded to the killing of 129 people two days earlier here, claimed by the IS in Syria. French President François Hollande said on Monday France was now at war with the ISIS and pledged further retaliation against the jihadist forces.

Ten fighter bombers — six Mirage 2000s and four Rafales — conducted the raid in coordination with the coalition, taking off at 1.30 a.m. (Paris time) last night from bases in Jordan and the Arabian Gulf, the ministry said. The aircraft dropped 16 bombs, destroying the two targets which had been spotted by French reconnaissance flights.

France launched the Chammal operation in September 2014 in response to a request from Iraq to help fight ISIS. The French forces committed 700 troops, six Rafales, three Mirage 2000D and three Mirage 2000N, and an Atlantique 2 maritime patrol aircraft. The Cassard frigate has been on station since Sept. 24 to support the mission.

Nuclear powered aircraft carrier Charles de Gaulle is due to sail out this week to support the operation with a further 24 fighters.

US secretary of state John Kerry met Hollande today, and said there was now greater cooperation in the Western-backed coalition against ISIS and the fundamentalist insurgents are losing ground.

"The level of cooperation could not be higher. We agreed to exchange more information and I'm convinced that over the next weeks, Daesch will feel greater pressure," he said, Reuters reported. Daesh is the Arabic name for ISIS.

"We gained more territory, Daesch has less territory," he said.

Hollande will meet US President Barack Obama next week for talks, Kerry said.

The French head of state said on Monday he would meet the US leader and Russian president Vladimir Putin and call for them to form a coalition against ISIS.

Hollande said Monday in a speech to both houses of parliament that France will seek "solidarity" from the European Union, and referred to article 42.7 of the EU treaty.

The treaty says in article 42 on a common defense and security policy: "If a Member State is the victim of armed aggression on its territory, the other Member States shall have towards it an obligation of aid and assistance by all the means in their power, in accordance with Article 51 of the United Nations Charter. This shall not prejudice the specific character of the security and defence policy of certain Member States."