France is not ruling out the prospect of sanctions against Iran over its nuclear program, which has made the international community "very worried," the French foreign minister said Sunday.

Philippe Douste-Blazy held out hope for a diplomatic solution before the April 28 deadline set by the U.N. Security Council for Iran to stop enriching uranium — which produces the fuel for either nuclear weapons or civilian power plants.

"If the response is negative, the Security Council will have to take its responsibilities, and sanctions are possible in the panoply" of options, Douste-Blazy said on Radio J.

"When I see this statement today that (Iran's) enrichment is irreversible, it's true we are very worried," he said, referring to comments by the Iranian Foreign Ministry earlier that a halt to nuclear activities was not on Tehran's agenda.