France orders tighter security after ramming attacks in US, Germany

Retailleau sought "optimal security conditions" in a memo to officials seen by AFP.

"Given the high level of terrorist threat weighing on our country, I ask you to maintain maximum vigilance and to reinforce security measures throughout the country for major festive, cultural and sporting gatherings," the minister said.

"The latest events in Germany and the United States show just how strong the threat is and how quick terrorists are to exploit any weaknesses," Retailleau added.

For events facing "an exceptional risk of terrorist threat", a decree may be issued so that access can be restricted by organisers, Retailleau said.

The minister said particular attention must be paid to the "training of security guards and approved personnel screening access or checking people."

Retailleau called for special advanced attention to traffic and evacuation plans and ensuring that "robust protection systems are put in place" against ramming attacks.

Six people died and 299 were injured after a car ploughed through a Christmas market in the eastern German city of Magdeburg in December.

On January 1, a US army veteran, who the FBI says pledged loyalty to Islamic State, used a pickup truck to kill 14 revellers in New Orleans.