Iran's President Mahmoud Ahmadinejad has written a letter to President Bush in a bid to ease global tensions, Iranian officials said Monday. This is the first such direct, high-level public communication between the two countries since Islamic revolutionaries took over the US Embassy in 1979.

The letter, which mentions Iran's contentious nuclear program, comes during a week when the US is trying to marshal key United Nations Security Council foreign ministers for a resolution that would compel Iran to suspend uranium enrichment - with the implied threat of sanctions and military enforcement. But Tehran says its program is legal and will continue.

Mr. Ahmadinejad's letter "spoke of the current tense situation in the world and suggested ways of solving problems and of easing tensions," Iranian government spokesman Gholamhossein Elham said Monday.

US Director of National Intelligence John Negroponte, who had not yet seen the letter being passed to Washington through the Swiss Embassy in Tehran, suggested that the "timing of the dispatch of that letter is connected with trying in some manner to influence the debate before the Security Council."

Taking a strident tone Sunday, Ahmadinejad warned of UN action: "They should know that the Iranians will dash their illegitimate resolution against the wall."

As this high-stakes diplomacy gets under way, the Monitor's Scott Peterson explores some basic questions about Iran's nuclear program:

Somewhere between two and 10 years. But the answer to that question depends upon whom you ask, and whether you accept that Iran will stick to a peaceful atomic energy program - as Iranian officials declare. Three years of UN inspections have not produced a definitive answer.

Some US politicians allege that the Islamic Republic is secretly trying to acquire nuclear weapons, and that mili- tary force can be used to stop any such work. But the International Atomic Energy Agency (IAEA), the UN nuclear watch- dog, has found no evidence of such a decision by Iran.

Mr. Negroponte, testified to Congress in February that Iran "will likely have the capability" to produce a nuclear weapon within 10 years.

In late March, the Institute for Science and International Security (ISIS), which closely tracks Iran's nuclear issues, calculated a "worst case" estimate of "at least three years" before Iran would have enough fissile material to make a bomb. The ISIS added that, "it could take Iran much longer" because of technical difficulties.

Some of the shortest estimates, of less than two years, come from Israel, which maintains its own unofficial nuclear arsenal. Many analysts argue that Iran has made no decision to build a weapon, but instead desires a "threshold" capability to make one within months.

Though American forces in the Middle East and Israel are within the 1,000-mile range of Iran's Shahab-3 missiles (Iran claimed upgrades to 1,240 miles in 2004), experts say that building a nuclear device small and light enough to be carried as a payload for such a distance is extremely tricky business.

US officials reportedly briefed the IAEA last July on designs it claims were found on a laptop - stolen by an Iranian, and acquired by US intelligence - which it said showed warhead designs modified to accommodate a compact nuclear warhead. US experts question the significance of the allegations, first reported by The New York Times last November. Iran rejects the charge as "a worthless attempt to fabricate a scenario," but the IAEA on April 28 reported that it is one issue Iran "has yet to address."

Page: 1 | 2 | 3