The new proposals have been agreed on by the five permanent members of the UN Security Council -- Britain, China, France, Russia, and the United States -- as well as Germany.
The contents of the package remain secret, but reports say it contains a wide range of concessions
, including an offer to supply at least one light-water nuclear reactor, trade deals, technology transfers, as well as the opportunity to buy Airbus and Boeing airliners.
"If you make a wrong move regarding Iran, definitely the energy flow in this region will be seriously endangered." -- Supreme Leader Ayatollah Ali Khamenei
U.S. Changes Tactics
Another major incentive is that the United States has expressed a willingness to talk directly with Iran about the nuclear dispute. This would mark the first face-to-face talks between the two countries since Iran's Islamic Revolution in 1979.
After two hours of talks with Solana, Iranian chief nuclear negotiator Ali Larijani indicated progress had been made. "We had constructive talks with each other," he said. "They presented proposals which they had worked on before. These proposals include positive steps and they also include some ambiguities that should be removed."
Solana said on arrival in Tehran on June 5 that the West is determined to open a new relationship with Iran based on confidence and faith.
"The proposals that we carry we think will be proposals that will allow us to get engaged in a negotiation based on trust, respect, and confidence," Solana said.
Punishment Also Part Of Offer
On the reverse side, the package also contains punitive measures which will be put before the UN Security Council for action if Iran rejects the incentives. They are likewise secret, but reports say they range from minor to harsh sanctions.
Solana said in Brussels on May 30 that Iran has no legitimate reason to reject the offer. He said if they do, that would confirm Western suspicions about Tehran's intentions.
"If they reject it, it probably will be once again a clear sign that what they are looking for is not only the production of energy, but [that] they are looking for a level of enrichment that goes way beyond what is necessary [for] the production of energy, entering into what we may call a nuclear-weapon type of enrichment," he said.
Is there disagreement within the Iranian government on how to proceed? (epa)
The Iranians reacted generally with restraint ahead of the formal receipt of the package today. But there were differences in the reactions of the various leaders, which analysts say could indicate disagreement in ruling circles on whether to accept or reject the offer.
For instance, Foreign Minister Manuchehr Mottaki struck an optimistic note in remarks to journalists on June 5. "If there is a political will to resolve the [Iranian nuclear] issue without any attempt to politicize it, I believe we can reach a compehensive agreement," he said.
On June 3, firebrand Iranian President Mahmud Ahmadinejad was milder than usual. He said Iran will carefully consider the latest proposals -- but at the same time he said it will never give up what he called Iran's "absolute right" to enrich uranium.
However, on June 4, Supreme Leader Ayatollah Ali Khamenei gave no ground at all, warning the United States not to use military means against his country, or it would suffer the consquences.
"If you make a wrong move regarding Iran, definitely the energy flow in this region will be seriously endangered," he said.
A much-used Iranian tactic during the nuclear dispute has been at every stage to appear willing to compromise, but always to return to an absolute refusal to give up uranium enrichment. It's not yet clear whether the latest encounter will follow that same pattern.
PRESIDENT TO PRESIDENT: On May 8, the Iranian government announced that President Mahmud Ahmadinejad had sent a letter to U.S. President George W. Bush. The letter was the first direct communication between leaders of the two countries since Iran's 1979 Islamic Revolution. RFE/RL has posted the English version of Ahmadinejad's letter that was posted on the Iranian president's website.
"The people will scrutinize our presidencies," AHMADINEJAD wrote. "Did we manage to bring peace, security, and prosperity to our people or insecurity and unemployment? Did we intend to establish justice, or just support special-interest groups and -- by forcing many people to live in poverty and hardship -- make a few people rich and powerful, -- thus trading the approval of the people and the Almighty for [that of those few]? Did we bring the world peace and security or did we raise the specter of intimidation and threats?"...(more)
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THE COMPLETE PICTURE: RFE/RL's complete coverage of controversy surrounding Iran's nuclear program.
CHRONOLOGY An annotated timeline of Iran's nuclear program.