French Prime Minister Manuel Valls on Tuesday urged the European Union to limit the number of migrants it allows into the bloc, following heightened security concerns after the Paris attacks.

"Europe must say that it can no longer accommodate so many migrants, it is not possible," he said in extracts from a lunch with foreign media published by Germany's Suddeutsche Zeitung.

A "binding" climate agreement with assurances of cash for developing nations will be the measure of success for a U.N. summit starting in Paris next week, French President Francois Hollande said Tuesday.

"The solution will be found in finance," Hollande told L'Express magazine on how to avoid deadlock at the summit tasked with curbing dangerous climate change.

France will install security gates at stations in Paris and Lille for the Thalys cross-Europe rail services by December 20 in one of a raft of measures introduced after the Paris attacks, minister Segolene Royal said Tuesday.

A Thalys train from Amsterdam to Paris was attacked by a heavily armed man in August, but he was overpowered by passengers.

French security forces have made nearly 300 searches in the Paris region since the jihadist attacks of November 13, police chief Michel Cadot said on Monday.

A total of 298 searches were made, Cadot said.

President Francois Hollande received strong backing from British Prime Minister David Cameron on Monday as global efforts to crush Islamic State gathered speed in the wake of the Paris attacks.

Speaking before he also meets the U.S., Russian and German leaders in the coming days, Hollande said Britain and France had a "joint obligation" to strike at the jihadist group.

French Defense Minister Jean-Yves Le Drian said Sunday that a chemical or biological attack "was among the risks" in the wake of the Paris attacks but that all possible precautions to avoid such a scenario had been taken.

He said French authorities were not ruling anything out in the wake of the Paris attacks even though it was "very complicated" for anyone to use chemical weapons.

Rival sides in chaos-ridden Libya must reach a deal to create a new unity government in order to stop Islamic State jihadists from taking over, the French defense minister said Sunday.

"There must be an intra-Libyan accord between these two rival factions, or else Daesh will win," Jean-Yves Le Drian told Europe 1 radio, using an Arabic acronym for IS.

EU ministers agreed Friday to get tough on border security after the devastating Paris attacks, as prosecutors said a third body had been found following a police raid on the ringleader's hideout.

Adding to fears about the global jihadist threat, gunmen seized 170 people in a hotel used by foreigners in the capital of Mali, with at least three hostages killed.

French Interior Minister Bernard Cazeneuve on Friday urged the EU to take urgent counter-terrorism decisions after having "wasted too much time", as he entered emergency talks following the Paris attacks.

"We hope that Europe, which has wasted too much time on a number of urgent issues, today takes the decisions that we must take," Cazeneuve told reporters as he arrived for a meeting with his EU counterparts in Brussels.

The suspected ringleader of the Paris attacks, Abdelhamid Abaaoud, was caught on camera at a Metro train station in the capital on the night of the carnage, a police source said Friday.

CCTV showed Abaaoud, who was killed in a police raid on an apartment on Wednesday, at a station near where police found a Seat car that was used in the coordinated wave of attacks last Friday that killed 129 people.