Is Iran serious about nuclear talks? West wants guarantees this time.

Western officials, repeatedly burned by Iran's pattern of accepting talks over its nuclear program only to buy time for further progress in uranium enrichment, are insisting upon guarantees that Iran is serious this time around.

That's why Secretary of State Hillary Rodham Clinton said Friday that Iran's acceptance of the latest invitation for talks – while offering signs of seriousness – will have to be studied further. 

Iran has not yet offered any promise to meet the preconditions that the West is demanding before talks begin. While Secretary Clinton did not list those conditions, a senior European official said in January that they include suspension of uranium enrichment and access for international inspectors to verify this.

Joining Clinton at the State Department Friday, the European Union’s foreign affairs chief, Catherine Ashton, offered only the most tentative of appraisals of Iran’s commitment.

“There is a potential possibility that Iran may be ready to start talks,” she said. “We’ll continue to discuss and make sure that what we are looking at is substantive.”

Iran's letter of acceptance, sent Wednesday, came in response to a letter of invitation to talks that Lady Ashton sent to Iran in October. In recent weeks, Iranian officials had hinted that Iran would accept a return to talks with a group of world powers. But they said Iran was ready to resume negotiations “without preconditions.”

Clinton on Friday said the US and other powers would require guarantees that Iran is prepared to meet its “international obligations” to limit its nuclear development to civilian purposes.

“We must be assured,” Clinton said, “that if we make a decision to go forward, we see a sustained effort by Iran to come to the table, to work until we have reached an outcome that has Iran coming back into compliance with their international obligations.”

Talks with Iran last sputtered out in January 2011 and haven’t involved any serious initiatives for addressing concerns about Iran’s nuclear program since October 2009. The talks involve Iran and the five permanent members of the United Nations Security Council (the US, China, Russia, the United Kingdom, and France) plus Germany.

In his letter to the EU, Iran’s chief nuclear negotiator, Saeed Jalili, spoke of his country’s “readiness for dialogue on a spectrum of various issues, which can provide ground for constructive and forward looking cooperation.” He alluded to the “Islamic Republic of Iran’s new initiatives in this round of talks,” without specifying what those “new initiatives” are.

French Foreign Minister Alain Juppé called the letter “ambiguous” and said the test of Iran’s seriousness about the talks would come next week when inspectors from the UN’s nuclear watchdog agency, the International Atomic Energy Agency (IAEA) are in Tehran.

“If Iran is really ready to discuss and show its sites and documents, then the conditions will be there to restart negotiations,” Mr. Juppé said.

The IAEA has been trying for years to gain full access to Iran’s nuclear facilities and documents. The IAEA says it has mounting evidence that Iran is not limiting its nuclear development to peaceful purposes, as Tehran claims, but is advancing parallel research and development in military applications.

Western countries are anxious about Iran’s advancing enrichment capabilities, and in particular about its growing stockpile of enriched uranium which, if it were to be enriched to higher purity, could be used to fuel a nuclear weapon.

But the West also feels that its increasingly draconian economic sanctions are beginning to bite the Iranian economy. It is this sense that sanctions are working that is allowing Western officials to play “cautious” about Iran’s offer to talk – until they get what they want.