Franco-German talks on European integration and harmony were rudely interrupted when a man appeared to confront the German Chancellor Angela Merkel.
Berlin radio said he was angry at new laws allowing personal information to be collected by the state.
Unruffled, the Chancellor and President Sarkozy went on to underline the close links between their two countries.
“We need to work together, to reinforce Franco-German friendship and relationships, especially with an eye on the younger generation,” she said.
“It’s alright to have disagreements between Germany and France, but they must be seen in context of the close working relationship between our two countries, and for Europe as a whole,” Sarkozy added.
The central theme of this visit is integration, and the two leaders reinforced that at a Berlin school whose pupils boast widely-differing backgrounds.
France and Germany are home to large immigrant populations, and the Chancellor and the President were keen to celebrate that diversity.