France, Britain, Germany, the United States, China and Russia hope that the threat of international sanctions will convince the Islamic republic to accept a package of economic, technological and political incentives in return for curbing its uranium enrichment drive.
John Limbert, a former US ambassador to Mauritania who taught in Iran in the 1960s and was in the US foreign service when he was taken hostage in Tehran in 1979, says the US and Iran need to find a different framework to deal with one another.
Limbert, who retired from the foreign service in April and was president of the American Foreign Service Association (2003-2005), worries that with each side believing the worst about the other, the chances of miscalculations and missteps will increase.
Aljazeera.net: What is the best approach to resolve the impasse between Iran and the US?
Limbert: The best case scenario is that the US and Iran move beyond the last 27 years of finger-pointing and mutual denunciations and start serious discussion of issues that concern both sides - including the issue of Iran's nuclear programme.
We don't have to like each other. But we should be talking to each other.
And the worst case scenario?
The worst case scenario is that the current downward spiral in relations continues and leads to each side misjudging the other.
Does this mean war?
Not necessarily, but when each side believes the worst about the other, then the chances of miscalculations and missteps will increase.
You were held hostage in Tehran for 444 days and some of the leaders of the group who took over the US embassy today are in influential positions. Is this a cause for worry in how Iran approaches the current crisis or will this help resolve the current standoff peacefully?
This situation is not new. A number of the hostage-takers, including former president Muhammad al-Khatami's brother, have held government positions during the last 25 years.
Their role is part of a larger problem - the failure of the Iranian authorities to take any responsibility for what happened [in the seizure of the US embassy and taking staff hostage] and their larger failure to have an honest discussion of those events.
Iran says it is enriching uranium because it is looking for alternative energy strategies. But the US says the Iranians are working on developing nuclear weapons. Where does the truth lie?
No one knows, but in the current situation each side is ready to believe the worst about the other. Until that downward spiral is broken - and there were some attempts a few years ago - each side will continue to assume the worst about the intentions of the other.
The recent perceived North Korean threat has raised alarms in Washington. Will this divert energy from dealing with Iran?
The two situations are obviously related, and each makes the other more complicated. We have two countries - with historically unpredictable regimes - that are ignoring world opinion. While each case is different, it is obviously more difficult to deal with two crises than one.
Could we see a military option exercised on Iran?
I personally believe armed conflict is a terrible outcome for both sides - a classic lose-lose result. But miscalculations on both sides could make it a reality.
How would that affect the Middle East given the crises in Iraq?
I can't predict how the Middle East would react, but it is very doubtful that many people there would welcome additional outside military action in the region.
What advice would you give US diplomats?
Be patient, firm, and keep the volume down. Avoid unfortunate phrases like "change their behaviour". Remember that the Iranian side comes to the table with numerous real or perceived grievances. Remember that we and the Iranians are like feuding neighbours. We may not like each other, but neither side is going away.
And Iranian diplomats?
Much of the above applies. Also, remember your country's over-riding national interests and do not overplay your hand. Remember that no enmity is forever.
Could the current crisis between Israel and Hezbollah, Iran's spiritual and military offshoot, affect the nuclear talks with Iran?
Clearly, the current tension on the border makes productive US-Iranian contacts more difficult. There's no evidence, but it's worth considering whether the crisis was deliberately provoked to sabotage any possibility of US-Iranian dialogue.
Will sanctions slapped on Iran solve the issue or add fuel to the fire?
There aren't many unilateral sanctions that the US hasn't already put on Iran. If there are, it is only because no one in Congress has thought of them yet.
International sanctions, however, will carry the important and symbolic message that Iran has - once again - turned potential friends into enemies.
And sooner or later, Iran will find - as it did in the 1980s - that it needs friends.