"We asked that the consultations be postponed not in order to revise the text but in order that we continue informal consultations that will take place in different configurations," Britain's UN envoy Emyr Jones Parry told reporters.

He said that he and his French counterpart, Jean-Marc de La Sabliere, felt there was no point in amending their draft if an agreement was not in sight.

"If there's no prospect for an agreed conclusion, we won't be amending the text," Jones Parry said.

Earlier a Western diplomat who requested anonymity said the formal council meeting was postponed to take into account Russian objections to the Franco-British draft.

He added that no new date has been set for a formal meeting.

"The Russians want a more general text, and no reference to the Iranian program being a threat to international peace and security, which could imply that the council might have to resort to sanctions," the Western diplomat said.

With Western countries suspecting Iran of seeking to acquire atomic arms, the council is debating a response to Tehran's defiance to demands that it halt uranium enrichment activities and open its doors to inspectors from the International Atomic Energy Agency (IAEA).

Western powers see adoption of the Franco-British non-binding statement by the 15-member council as the first step in a graduated response that could ultimately lead to sanctions against Tehran.

Diplomats in Vienna said that if the council fails to agree on the non-binding Franco-British text, the US delegation might push for a tough UN resolution invoking possible sanctions under Chapter 7 of the UN charter.

Asked if a draft resolution was on the table, Jones Parry replied: "the idea of anything is on the table if it produces a satisfactory outcome and sends the right message to Tehran."

Iran denies claims that it is seeking nuclear weapons and insists that as a signatory of the nuclear Non-Proliferation Treaty it has a right to conduct uranium enrichment.

The Security Council had been due to review the Franco-British draft Tuesday a day after a six-nation meeting in New York failed to yield agreement on the text and on a broader strategy to deal with Tehran.

Another Western diplomat, who spoke on condition of anonymity, described a six-nation gathering Monday as "difficult", largely because of Russian and Chinese objections to the firm stance advocated by the Western powers.

That meeting brought together top officials from Britain, China, France, Russia and the United States -- the council's five veto-wielding permanent members -- and Germany, one of three European powers that have been pursuing inconclusive nuclear talks with Tehran.

US ambassador John Bolton said that he expected a new formal session of the full council to be convened "in the next couple of days".

Meanwhile US President George W. Bush warned Tuesday that a nuclear-armed Iran "could blackmail the world." But he also reaffirmed that he wanted a diplomatic solution and that his government would continue to let Britain, France and Germany lead international talks with Iran.

Chinese ambassador Wang Guangya for his part called for more time for diplomacy to work, while stressing that the Security Council needed to take some action soon.

Russian Foreign Minister Sergei Lavrov said the Security Council should "at this stage limit itself to supporting the efforts of the IAEA and cooperating with it to clarify remaining questions," according to the ITAR-TASS news agency.