Olympic opening ceremony in Paris may be moved from river to stadium for security reasons

French President Emmanuel Macron on Monday said the opening ceremony for the Paris Olympics planned on the River Seine could be shifted instead to the Stade de France if the security threat is deemed too high.

France is on high security alert ahead of the Paris Olympics and Paralympics, which are expected to draw millions of visitors to the country.

Security concerns are notably high for the exceptional opening ceremony, which involves boats carrying athletes along the Seine on a six-kilometre parade and huge crowds watching from the embankments.

Speaking to French media BFM-TV and RMC, Macron said France's law enforcement forces will be mobilized at an exceptional level for the security of the open-air event.

"But if we think there are risks, depending on our analysis of the context, we have fallback scenarios," Macron said. "There are plan Bs and plan Cs."

The July 26 event is set to be the first Olympic opening ceremony held outside a stadium setting. About 10,500 athletes will parade through the heart of the French capital on boats on the Seine along the route ending in front of the Trocadero.

To limit security risks, Macron said organizers could decide to shorten the itinerary of the parade on the Seine, and even to "repatriate the ceremony to the Stade de France" for a more conventional opening event.

Organizers had originally planned a grandiose opening ceremony for as many as 600,000 people, most watching free of charge from riverbanks. But security and logistical concerns have led the government to progressively scale back its ambitions. Earlier this year, the overall number of spectators was reduced to around 300,000.

The French government also decided that tourists won't be given free access to watch the