"The key word for us is the unity of the international community," Douste-Blazy told journalists after meetings with his Chinese counterparts in Beijing.
"Faced with this unity, Iran also faces a strategic choice… either isolation or the suspension of its sensitive nuclear activities."
His comments came with the UN Security Council mulling a second sanctions resolution against Tehran, with Russia and China less enthusiastic than the United States and Britain over harsher measures.
"The role of France is to form a balance between the Americans and the British who want more sanctions and the Russians and the Chinese who do not want such a level of sanctions," he said.
The five nations are the sole permanent members of the Council and all have veto power.
Douste-Blazy met Prime Minister Wen Jiabao and Foreign Minister Li Zhaoxing on Wednesday.
China’s foreign ministry refused to elaborate on the new resolution but Li discussed the issue with Iranian Deputy Foreign Minister Abbas Eraqchi in Beijing on Thursday, the official Xinhua news agency reported.
Iran defied a previous Council resolution to suspend uranium enrichment, setting up the possibility of further action.