"Iran is pursuing the development of its nuclear arms, I have no doubt about it," Juppe told French television station i-Tele. "The last report by the International Atomic Energy Agency is quite explicit on this point."
France, Juppe said, wants tougher sanctions "without closing off the path of negotiation and dialogue with Iran," Radio France Internationale reported
He said French President Nicolas Sarkozy has proposed freezing assets of Iran's central bank and placing an embargo on Iranian oil exports, which the EU also is considering.
Juppe noted U.S. President Barack Obama had signed into law tough sanctions on Iran's central bank and financial sector.
"We hope that the Europeans, by Jan. 30 will take equivalent measures to show our determination," Juppe said.
Iran, which maintains its nuclear program is for peaceful purposes only, test-fired missiles near the key Gulf oil supply route of the Strait of Hormuz in recent days, heightening tensions.
Iran called on the European Union to schedule new nuclear negotiations. But before talks can resume, the bloc said Tuesday, Iran must first respond to an October letter from European Union Foreign Policy Chief Catherine Ashton proposing renewed talks.