"I invite the Iranian authorities to make the choice of cooperation and trust by genuinely looking at this offer and by reverting to their commitments to suspend activities linked to the production of fissile materials," Chirac said in a speech on Monday.
Chirac said negotiations could still be held with Tehran but that if it did not cooperate, the United Nations Security Council would have to examine the issue.
"There is room for dialogue and negotiation," he said in a speech to French ambassadors meeting in Paris to discuss France's foreign policy.
"We urge Iran to show a spirit of responsibility to re-establish cooperation and trust, without which the Security Council will have no choice but to examine the question."
Iran said on Friday it hoped to present a plan within a month to head off EU preparations to refer it to the Security Council for possible sanctions, but diplomats interpreted the move as stalling.
"I invite the Iranian authorities to make the choice of cooperation and trust by genuinely looking at this offer and by reverting to their commitments to suspend activities linked to the production of fissile materials"
French President Jacques Chirac
Diplomats who follow the International Atomic Energy Agency (IAEA), the UN's nuclear watchdog, said Iran appeared to be stalling for time, as the EU trio were likely to push for Iran to be referred to the UN Security Council in less than a month, when the IAEA governing board meets on 19 September.
Iran rejected the offer of European incentives earlier this month and resumed some nuclear work, in breach of a promise to freeze such activities while talks lasted, prompting the EU trio of Britain, France and Germany to call off a negotiating meeting with the Iranians.
The EU and the US suspect Iran of secretly trying to build nuclear weapons. Iran says it wants nuclear technology only to cope with booming electricity demand.