Locals gathered to grieve for those killed in the recent terror attack.
Prime Minister John Key was at the Australian Embassy in Paris watching an fireworks display on Bastille Day when he heard news about the "horrific" attack in Nice of innocent people watching fireworks themselves.
"France has gone from amazing celebration and a great sense of pride to being plunged rightback to where they were last year," Key said from Paris where two other big terrorist attacks have occurred in 18 months.
Key said New Zealand deeply sympathised with the people of France.
"We feel their pain and we are there to give them every encouragement we can as they regroup," he told the Weekend Herald.
"We understand not only how tragic it is but how difficult it is to get used the random and brutal nature of these attacks. But ultimately we will stand in solidarity to support them."
Just hours earlier Key had held talks with French President Francois Hollande and Prime Minister Manuel Valls.
Key and his wife Bronagh and children Max and Steffie, who lives in Paris, had been special guests for the July 14 parade on the Champs Élysée featuring Kiwi and Australian military.
Asked if the attacks made him feel nervous having his daughter living in France, he said he thought her attitude had changed in the past eight months.
"She is a lot more conscious of the threat of terrorism and certainly amongst her circle of friends, the reality is they are just going out a lot less.
"I'm always conscious of the fact that you'd have to be so desperately unlucky to be caught up in one of these attacks, but even so, it plays on people's minds."
Key said he had been at the Australian Embassy because it had the best view of the Eiffel Tower in all of Paris.
"It is unbelievable," he said. "In fact so much so that I sent Malcolm Turnbull a text to stay Federation[with Australia] would have at least one advantage."
Australian Governor General Sir Peter Cosgrove represented Australia at the parade because Prime Minister Malcolm Turnbull is still forming a Government.
Key and Cosgrove watched the television to get her at the embassy to try to get more details and Key said he heard what he thought were controlled explosions near by - although it has not been confirmed that they were explosions and not fireworks.
"But it took a while leave because they put Paris into a bit of a lockdown.
"It took a while to get home."
Authorities investigate the truck involved in the attack. Photo / AP
Key said there was a lot of pride watching the New Zealand Defence Force march down the Champs Élysée.
"Bastille Day for them is about a celebration but equally there was a somber part of it as people reflected on the enormous losses." Troops had been there as a recognition of the enormous sacrifices individual families and communities had made in battles in wars.
Key said he had 'a great meeting" with Hollande and Valls before the attack.
"It was very warm and very forward leaning."
Instead of any hesitancy that New Zealand might have anticipated on the part of the French for a free trade agreement between Europe and New Zealand in light of Brexit "they are very much wanting to get going."
"So it's an interesting change, a discernible change."
