France is to reinstate border controls for a month around a major UN climate conference.
The controls are part of larger security measures around the conference, which is taking place between November 30 and December 11, according to interior minister Bernard Cazeneuve.
Authorities are on alert for violent protesters as well as potential terror attacks.
France faced deadly attacks by Islamic extremists in January and several other smaller attacks or attempted attacks so far this year.
The conference is aimed at reaching the most ambitious global accord to date for all world governments to reduce emissions that cause global warming.