By Sarah Shenker
BBC News, Paris
The French "No" camp was jubilant as members flocked to celebrate at Paris' Place de la Bastille.
The "No" camp brought together the radical left and right
Despite the drizzle, the mood was vibrant as a crowd of about 500 cheered to the sound of beating drums.
Communist activists waved their flags and made impromptu speeches. Graffiti such as "Chirac - 10 years is enough" was daubed on the Bastille monument.
There was only one topic of conversation in the cafes where activists sought shelter and toasted victory.
Hanane hoped the government and President Jacques Chirac would resign following France's rejection of the planned EU charter.
"I don't think national politics and the constitution are separate issues," the 26-year-old said.
"Most of this government's economic policies have come from Brussels."
Fellow reveller Yannick Delaunay saw France's "No" as a chance to "build something different".
"The French have said 'No' and it is a great moment," the 52-year-old said.
"We're going to have a great party tonight."
The mood at the headquarters of the ruling UMP was strikingly different.
As leaders talked to selected members of the media inside, activists were shut out on the street because of overcrowding.
Outside, Stephane Thomas was "really disappointed" by Sunday's result.
"We will have a much weaker Europe now," the 19-year-old student said.
"And I'm sad for the 45% of French people who voted 'Yes' and believed in the European project."
The atmosphere was also flat at the opposition Socialist Party headquarters, where workers and reporters awaited party leader Francois Hollande.
Management consultant Hocine Merrir was the only person willing to share his thoughts on the result.
"I'm very disappointed because my impression is that the French voted not for the right reasons, but against the government," the 23-year-old said.
"My only hope is that we don't suffer any major consequences. I hope we're not going to be thought of like the British.
"France is not in good shape - but it's not because of Europe."