The United Nations' Security Council approved a third round of sanctions against Iran over its refu-sal to suspend its uranium enrichment programme with almost unanimous support yesterday.

All but one of the members voted for the introduction of additional measures to those imposed in 2006 and 2007, with only Indonesia abstaining.

Western powers, including Britain, suspect Iran may be developing nuclear weapons, but Iran says its nuclear programme is designed for peaceful power generation only.

Sir John Sawers, the UK's permanent representative to the UN, said the move sent a "clear message" to Iran over its nuclear programme.

, which he said "only makes sense as part of a plan to develop, at the least, a nuclear weapons capability".

"Overall, Iran has clearly failed to abide by its legal obligations under successive Security Council resolutions," Sir John said.

He told the Security Council it was a "matter of great regret" that for the past 20 months Iran had ignored an offer which "would give Iran everything it needs to develop a modern civil nuclear power programme, including legally guaranteed supplies of nuclear fuel".

Sir John went on: "Iran's leaders should listen to what the international community is saying rather than misleading their people by misrepresenting our actions and misrepresenting the (UN's nuclear watchdog, the International Atomic Energy Agency) IAEA's reports on their nuclear programme."

He said Iran's leaders had a clear choice between cooperating with the international community "or to pursue their nuclear programme in disregard of international concerns and worsen still further their international isolation".

"The choice is for Iran's leaders to make," he said.

"The British Government hopes they take the positive path; the Iranian people deserve no less."

He added: "If Iran does not take this opportunity, then, as the resolution makes clear, the Security Council is committed to implementing further additional measures."

Mohammad Khazee, Iran's UN Ambassador, said his government would not comply with the "unlawful action" against its "peaceful nuclear programme".

"Iran cannot and will not accept a requirement which is legally defective and politically coercive," he said.

"History tells us that no amount of pressure, intimidation and threat will be able to coerce our nation to give up its basic and legal rights."

For the first time, the resolution bans trade with Iran in goods that have both civilian and military uses.

It also authorises inspections of shipments to and from Iran by sea and air that are suspected of carrying banned items.

The resolution introduces financial monitoring of two banks with suspected links to proliferation activities, Bank Melli and Bank Saderat, and calls on all countries "to exercise vigilance" in entering into new trade commitments with Iran, including granting export credits, guarantees or insurance.

The resolution also orders countries to freeze the assets of 12 additional companies and 13 individuals with links to Iran's nuclear or ballistic missile programmes and imposes a travel ban on five individuals linked to Iran's nuclear effort.

One of these individuals is Brigadier General Mohammad Reza Naqdi, a prominent figure in the elite Revolutionary Guard military corps who is close to Iran's supreme leader Ayatollah Ali Khamenei.

The resolution identifies him as a former deputy chief of the Armed Forces General Staff for Logistics and Industrial Research and as head of the State Anti-Smuggling Headquarters engaged in efforts to get around previous UN sanctions.

Britain and France, who co-sponsored the resolution, put off the vote from Saturday until today to try to get on board four non-permanent Council members who raised a variety of concerns - Libya, Indonesia, South Africa and Vietnam.

Only Indonesia abstained in the final vote, with its ambassador Marty Natalegawa saying his nation had confidence in the IAEA, to be able to handle the dispute over Iran's nuclear programme, rather than the Security Council intervening with further sanctions.

Last month, the IAEA reported that suspicions about most past Iranian nuclear activities had eased or been laid to rest.

But the IAEA has criticised Iran for refusing to clarify remaining questions about intelligence, suggesting Tehran may have been exploring ways to "weaponise" nuclear materials.

The IAEA also reported that Iran rejected new documents that link Tehran to missile and explosives experiments and other work connected to a possible nuclear weapons programme.

Iran called the information false and irrelevant, the IAEA said.