"Faced with an event this big... which must take place in conditions of security and which at the same time should be a celebration.... we have to ensure security," he said on France Info radio.
"The state of emergency cannot be permanent but on the occasion of these big events... we have decided to prolong [it]."
The current state of emergency giving extra powers to police and security forces runs until May 26. The month-long Euro 2016 soccer tournament hosted by France starts on June 10.