UNITED NATIONS — In a sign that U.N. Security Council-based diplomacy is losing steam, a number of sources are reporting that a military strike against Iran’s nuclear facilities may be imminent. France and America also are pushing for tighter economic sanctions against Tehran, without U.N. approval.

Yesterday’s edition of Le Canard Enchaîné, a French weekly known for its investigative journalism, reported details of an alleged Israeli-American plan to attack Iran’s nuclear facilities. The frontpage headline read: “A report sent to the Elysée — Putin tells Tehran: They’re going to bomb you!”

The Saudi foreign minister, Prince Saud al-Faisal, also expressed concerns to reporters in New York that an attack on Iran might be imminent.

Like most stories in the French paper, the article was based on unnamed sources who said that in order to reduce casualties, the attack against Iran is planned for October 15, the end of the Muslim holy month of Ramadan. Israel would bomb the first targets while America would orchestrate a second wave of strikes, the report said.

However, the French foreign minister, Bernard Kouchner, who recently spoke of preparing for war with Iran, berated reporters yesterday, telling them that he had said war is the “worst option.” Instead, he is now calling for “diplomacy, diplomacy, diplomacy.”

As foreign ministers representing the five permanent members of the Security Council — China, Russia, France, Britain, and America — and Germany plan to sit down Friday for a long-planned meeting to discuss ideas for addressing Iran’s refusal to end uranium enrichment, Mr. Kouchner told reporters that China and Russia are likely to delay any significant decision until at least December.

“It would be very difficult to convince the Russians and the Chinese before” December, he said. A Russian diplomat told The New York Sun on Monday that Moscow would call on the council to await the conclusion of a new round of diplomacy conducted by the director of the International Atomic Energy Agency, Mohamed ElBaradei.

At a breakfast with reporters yesterday, Mr. Kouchner said he had “spent hours” with the Russian foreign minister, Sergey Lavrov, trying to convince him to approve council sanctions against Iran. Russia, Mr. Kouchner said, is attempting to regain its top world status, while “we treat them, they told me, like little adolescents.”

Meanwhile, a former American ambassador to the United Nations, John Bolton, indicated yesterday that President Sarkozy of France may be a more reliable ally on Iran than Prime Minister Brown of Britain.

“It’s not at all clear where Brown is at,” Mr. Bolton told the Sun. “The question is, ‘Will Britain follow in the footsteps of France?'” Either way, Mr. Bolton said he did not invest too much hope in Security Council diplomacy.

Some American diplomats are saying the next phase of diplomacy with Iran may involve a separate track of sanctions that would be imposed without Security Council approval.

Mr. Kouchner said yesterday that the French government is trying to lean on companies like the oil giant Total to end ties with Iran. Between 2005 and 2006, he said, French commerce with Iran was cut in half.

But an unnamed German government official told Reuters yesterday, “Unlike the United States and the French, the German government is not ready to go outside the U.N. for sanctions.” The official expressed doubts that Europe could reach a consensus on such sanctions. German companies such as Siemens, BASF, Mercedes, and Volkswagen maintain strong business ties with Iran. In 2006, such companies reportedly exported goods worth $5.7 billion to Iran, up from $5 billion in 2004. In Vienna, Mr. ElBaradei is preparing a report that is not expected to be ready before December. In a speech to the U.N. General Assembly earlier this week, President Ahmadinejad of Iran said the “nuclear issue of Iran is now closed,” and he said Tehran would stop dealing with the Security Council and would negotiate only with the IAEA.

Mr. ElBaradei recently reached an agreement with Iran that allows it to report on outstanding nuclear issues over a long period of time. The Iranians, nonetheless, are “very, very, very firm that they don’t want to stop enrichment,” Mr. Kouchner said yesterday.

Mr. ElBaradei, who is charged with reporting on technical nuclear issues, was berated by Secretary of State Rice, who said the Tehran accords amounted to conducting private diplomacy.

Before he became U.N. ambassador, Mr. Bolton sought to mount a campaign to unseat Mr. ElBaradei. A former secretary of state, Colin Powell, “was never enthusiastic about it,” Mr. Bolton said yesterday. “When Rice became secretary of state, the winds came out of the sails” of the campaign to unseat the IAEA director. “Stopping him would have required a lot of effort,” Mr. Bolton said, but he added that Mr. ElBaradei’s current behavior on Iran “proves that it was worthwhile.”