Iran and six world powers, including the U.S., unveiled a historic deal aimed at ensuring Iran does not develop nuclear weapons in exchange for the easing of economic sanctions. Here are some highlights from Tuesday's agreement:
Will Iran keep a nuclear program?
Yes. The plan allows Iran to retain its nuclear program for purely peaceful purposes — including electricity and for medical treatments. Tehran has agreed to certain limits on all uranium enrichment and related research and development for the first eight years of the agreement.
“Iran reaffirms that under no circumstances will Iran ever seek, develop or acquire any nuclear weapons," according to a text of the agreement released Tuesday.
What happens to Iran's existing stockpile of nuclear materials?
Iran has promised to reduce its stockpile of low-enriched uranium — 3.67 percent enriched or less — by around 98 percent to under 300 kg (about 660 lbs) for 15 years. Anything beyond this will be sold and sent abroad. According to the State Department, Iran had been enriching uranium to a level of 20 percent. That's far below the 90 percent typical threshold for weapons-grade material.
Will sanctions be lifted?
Under the deal, all U.N. Security Council sanctions will be lifted, as will other sanctions placed on the country. International sanctions — which had barred Iran from selling its oil abroad and kept it out of the international financial system — have caused Iran's economy to shrink by 20 percent, according to the U.S. government.
It could be months before Iran starts to feel the effect of sanctions being lifted, but once that happens, the country will gain access to some $100 billion in frozen assets.
Who makes sure Iran sticks to the deal?
The International Atomic Energy Agency (IAEA) will monitor and verify that Tehran abides by the agreement and, according to the State Department, will maintain a "long-term presence in Iran."
The IAEA announced that it had agreed to resolve its own outstanding issues by the end of 2015. The main deal relies on the IAEA being able to inspect Iranian nuclear sites and on Iran answering its questions about possible military aims of previous research.
What if Iran violates the agreement?
The time it would take Iran to develop enough weapons-grade nuclear material to make one bomb is known as the "breakout period." Under the agreement, Iran would need at least one year to do so for the next decade.
Tehran also agreed to a "snap back" mechanism, under which sanctions would be reinstated if it violated the deal, according to the U.S.
Will Tehran be able to buy weapons on the international market?
A United Nations weapons embargo will stay put for five years, while a missile technology ban will remain for eight.
What happens to Iran's nuclear facilities?
Iran pledged to convert its Fordow facility into an international nuclear, physics and technology center.
"International collaboration including in the form of scientific joint partnerships will be established in agreed areas of research," according to the agreement.
Iran will be allowed to rebuild and modernized its heavy water research reactor in Arak. Its reactor will be used for peaceful research and medical purposes, and will not produce weapons-grade uranium, according to the agreement.
The Republican-controlled Congress has 60 days to review the agreement. Republicans have objected to the deal but President Barack Obama has said he would use his veto to override any resolution of disapproval. The agreement will also need Iran's supreme leader to ratify it. He may face opposition from hardliners in Iran.
It will also have to be ratified by the U.N. Security Council.
Do we have more summits to look forward to?
Ministers from the world powers and Iran will meet at least every two years — or more, if necessary — to review how things are going.