"We should give Iran one last chance for dialogue," French Foreign Minister Bernard Kouchner said in an interview published on Monday in Le Figaro.
According to Kouchner, "Economic sanctions that would be imposed on Iran would be very harsh, but we are not there yet."
The French foreign minister expressed concern about Iran's actions.
"Why did Iran announce 10 new uranium enrichment sites when it has only one nuclear plant to burn this fuel?" The fact that Iran persists in ignoring the demands of the IAEA, that's very dangerous," he said.
Regarding tensions between Israel and Iran, Kouchner said "direct confrontation between the countries must be avoided as it would have incalculable consequences."
In a separate interview Monday with France's RTL radio Kouchner called Iran's decision on the new nuclear sites "a bit childish."
"Iran is playing an extremely dangerous game," Kouchner said on France's RTL radio. "There's no coherence in all this, other than a gut reaction."
Meanwhile, Iran's nuclear chief said UN criticism pushed his country to retaliate by announcing the ambitious plans to build 10 new uranium enrichment facilities.
Vice President Ali Akbar Salehi told state radio that the decision was necessary to respond to the International Atomic Energy Agency's resolution Friday demanding that Iran halt all enrichment activities.
The bold announcement appears to be largely bluster: Any new plants would take years to build and stock with centrifuges, if Iran can even afford it or obtain the materials while under UN sanctions. But the ambitious plans demonstrates Teheran's anger over the IAEA rebuke and its refusal to back down in the standoff despite sanctions threats.
Iran and the top powers at the UN are deadlocked over a UN-drafted proposal for Iran to send much of its enriched uranium abroad, which the West seeks because it would at least temporary leave Teheran unable to develop a nuclear bomb. So far Iran has balked at the offer. The unusually strong IAEA censure of Iran over enrichment was a sign of the West's growing impatience with its defiance.
French Defense Minister Herve Morin said that after Iran's enrichment announcement Sunday the international community should "probably commit toward new economic sanctions against Iran."
"It's clear for weeks that the extended hand of Barack Obama and the extended hand of the international community, in an approach of transparency ... are not working," Morin told France-Inter radio Monday.
But Russia's energy minister, on a visit to Iran on Monday, maintained there was still a good chance for negotiations to resolve the crisis.
Sergei Shmatko urged Iran to continue cooperating with the IAEA and talking with the US and its allies.
"We are not interested in the deterioration of the situation at all," he said. "There are good capacities for the continuation of talks."
Iran's parliament speaker Ali Larijani also insisted "a diplomatic opportunity" was possible "under which Iran will continue its (nuclear) work under international surveillance."
But a day earlier, Larijani warned that Iran could reduce its cooperation with the IAEA if the West continues its pressure and doesn't compromise. Larijani did not elaborate, but such steps could include a lessening of UN inspections and monitoring of Iran's nuclear facilities - a move that would escalate the standoff since the monitoring is the world's only eyes on the program.
Iran says its nuclear program is peaceful, insisting it has a right to uranium enrichment to produce fuel for nuclear reactors to generate electricity. The United Nations has demanded Iran freeze enrichment, because the process can also be used to develop a warhead. The US and its allies accuse Iran of secretly planning to build a weapon.
The sharply worded IAEA resolution on Friday repeated demands Iran halt all enrichment and stop construction on a newly discovered enrichment facility that has been under construction for years at Fordo, near the Iranian city of Qom.
Iran has one operating enrichment facility, at the central town of Natanz, which has so far produced around 1,500 kilograms (3,300 pounds) of low-enriched uranium over the past years. That is more than enough to produce a warhead if Iran decided to enrich it to a higher level.
On Sunday, the Iranian Cabinet ordered the Atomic Energy Organization of Iran to begin building new enrichment facilities at five sites that have already been studied and propose five other locations for future construction within two months. The new sites are to be on the same scale as Natanz.
Salehi, who is also the head of Iran's nuclear program, said the IAEA resolution backed by six world powers left no option for Iran but to give a firm response.
"We had no intention of building many facilities like the Natanz site, but apparently the West doesn't want to understand Iran's peaceful message," Salehi said.
Iran aims to generate 20,000 megawatts of electricity through nuclear power plants in the next 20 years. Iranian officials say the new enrichment facilities are needed to produce enough fuel for its future nuclear power plants - though the country currently does not have a single operating power reactor.
The UN-brokered plan at the focus of Western diplomatic efforts aims to reduce tensions by requiring Iran to send 1.2 tons (1,100 kilograms) of low-enriched uranium - around 70 percent of its stockpile - to Russia in one batch by the end of the year. That would leave Iran without enough material to further enrich for a warhead.
In return, Russia and France would further process the low-enriched uranium into fuel rods to be returned to Iran for use in a medical research reactor in Teheran.
Iran has yet to give a cohesive answer, officials in Vienna say, but appears to be balking at some of its provisions. The US and its allies have so far insisted that Iran accept the deal as is.
But Iran's foreign minister has spoken of a counterproposal by which a simultaneous swap would occur on Iranian territory: The fuel rods would be brought to Iran, exchanged for the low-enriched uranium, which would then be taken out of the country.
In Vienna, a diplomat from one of the six world powers engaging Iran on its nuclear program said that scenario - if it entailed exchanging the full 70 percent of Iran's stockpile at once - would be acceptable to his country. But he noted that Iran has not formally proposed the idea and was giving conflicting signals. He spoke on condition he and his country not be identified because of the sensitivity of the situation.
Iranian officials have also threatened to drop the deal completely and process the fuel rods themselves from the uranium. Salehi said the Iranian Cabinet will discuss that possibility in a session Wednesday, but didn't give any further details.