France would “intensify” airstrikes against the group and “choose targets that will do the most damage possible to this terrorist army”, Hollande said during a joint news conference in Paris.
He added: “We also have to act in Syria. France has taken this decision in the month of September. It is up to the U.K. how it can also engage but we are convinced that we must continue to hit Daesh in Syria.”
Cameron also announced he had offered Hollande access to a British air base situated in Cyprus, just 250 kilometres from Syria.
“I strongly support the decision of President Hollande to hit ISIL [Daesh] in Syria,” Cameron said. “It is also my firm belief that the U.K. must do the same too, a step that will be decided by the parliament.
“President Hollande and I are united in our determination to defeat the evil death cult, ISIL.”
The U.K.’s Ministry of Defence said Royal Air Force Akrotiri base would be available as an “emergency diversion airfield” to support the Charles de Gaulle aircraft carrier, which arrived in the eastern Mediterranean on Monday. French fighter jets will not launch direct strikes against Daesh from Cyprus.
Cameron needs the British parliament’s approval to conduct air attacks in Syria against Daesh, as it is doing in Iraq.
U.K. lawmakers rejected a proposal to launch Syrian airstrikes in 2013 when President Bashar al-Assad’s forces were to be the target. Now Daesh is seen as the main threat in the country and on Sunday Chancellor George Osborne told broadcaster BBC the issue would be put to parliament this week.
Hollande, Cameron and Paris Mayor Anne Hidalgo visited the Bataclan concert hall earlier Monday. They each placed a rose among the floral tributes outside the venue, where 90 people were killed in suicide attacks on Nov. 13, including the only British fatality.
On Sunday evening, French police issued a photograph of one of the suicide bombers thought to have killed himself outside the Stade de France — one of the sites of the Paris attacks that killed 130.
In Belgium, prosecutors announced Monday that police had arrested 16 people in 22 raids carried out Sunday. Suspected attacker Salah Abdeslam was not among them.