French President Emmanuel Macron has said authorities will have an alternative plan in case of a terrorism threat at the Paris 2024 Summer Olympics Opening Ceremony.

“If we think there are security risks, we’ll have plan B, and even plan C,” Macron said in an interview with CNN affiliate BFMTV from The Grand Palais in Paris, one of the Olympic sites, during a visit Monday to mark 100 days before the opening of the games.

Macron mentioned the option of “restricting the ceremony to the Paris Trocadero square facing the Eiffel Tower” or moving it to the Stade de France stadium.

The president added that authorities will put a security perimeter around the ceremony site days, if not weeks, before the start.

Earlier in March, French Interior Minister Gérald Darmanin announced that the attendance capacity at the ceremony – the first to be held along a river – will be halved due to security reasons.

Some 104,000 people in stands will line Paris’ Seine river, with a further 220,000 on raised roadways along the six-kilometer (nearly four miles) stretch of the river that will host the ceremony, according to the French interior ministry.

French officials had boasted for years that some 600,000 people would be able to attend the Opening Ceremony.

Last week, Paris police boosted security measures for the Champions League quarterfinal between Paris Saint-Germain and Barcelona.

The heightened security presence followed a threat from the Islamic State terror group against the Parc des Princes and other European soccer stadiums hosting Champions League matches.