Here’s What You Need to Know About the Iran Deal

After 18 months of drawn-out negotiations, the U.S. and its partners on Thursday arrived at an agreement on a framework for curbing Iran’s nuclear capabilities.

If that sounds tentative, that’s because it is. The two sides have until June 30 to hash out the details of a final agreement. As President Barack Obama warned following the announcement of the latest progress, “there will be no deal” if Iran backtracks.

But the agreement sets the stage for a comprehensive deal that the U.S. and its allies believe could prevent Iran from building nuclear weapons in the near future, while providing relief to Iran’s limp economy. Here’s what you need to know about the ongoing talks:

What does the U.S. and its partners want?

The U.S. side consists of U.N. Security Council members Britain, China, France and Russia as well as Germany (dubbed the P5+1). They are pressing for restrictions that will extend the amount of time it will take Iran to build a nuclear weapon — the so-called “breakout time” — from the current 2-3 months to a year. To do that, the P5+1 are pushing to reduce the number of centrifuges Tehran can use to enrich uranium into fuel for a nuclear weapon, as well as cut its stockpiles of enriched uranium. Meanwhile, the U.S. and its partners are demanding monitors to continuously inspect Iran’s nuclear program.

What does Iran want?

Iran is keen to see the removal of sanctions to ease pressure on its struggling economy and gain access to the international market. But it insists that it has the right to nuclear capabilities for energy and medical purposes and is unwilling to scrap its nuclear resources altogether.

So what does the framework agreement say?

According to the framework agreement, Iran agreed to cut by two-thirds its supply of centrifuges, from roughly 19,000 to about 6,000, and retain only its earliest generation centrifuges. It said it would keep continuing enrichment far below levels necessary for a nuclear weapon and also agreed to reduce its stockpile of enriched uranium by 97%.

But exactly how it plans to scrap its extra centrifuges and enriched uranium is the kind of question negotiators will be answering over the next three months. Finally, Tehran pledged to give the International Atomic Energy Agency access to all of its nuclear facilities and to its nuclear supply chain. “If Iran cheats, the world will know,” Obama said.

The U.S., the United Nations and the European Union will lift nuclear-related sanctions once Iran is deemed to have complied with its side of the bargain; American sanctions related to terrorism, human rights abuses and non-nuclear weapons will remain in place. Meanwhile, the U.S. will be poised to “snap-back” nuclear sanctions if Iran backpedals.

What do opponents of a deal say?

Israeli Prime Minister Benjamin Netanyahu, who has been a staunch critic of the negotiations, came out swinging after the framework agreement was reached. “The proposed agreement would constitute a real danger to the region and the world, and it would threaten the existence of Israel,” said Netanyahu, who was re-elected last month. An official close to his office went even further, saying the framework agreement “kowtows to Iranian dictates.”

Opponents say in part that a one-year breakout time is insufficient, giving the U.S. and its allies too little time to react if Iran does race to build a nuclear weapon. They also raise concerns that no matter what access Iran gives IAEA inspectors, they could still attempt to build a weapon without inspectors or U.S. intelligence finding out. “We are all concerned that the Iranians will circumvent the deal,” said Israeli politician Yair Lapid, a leading Netanyahu opponent who still says the deal is troubling to all Israelis.

In the U.S., Republicans, with some support from Democrats, have lined up a bill that will effectively require Congressional approval for a nuclear deal by giving legislators the power to reject lifting sanctions on Iran. The White House opposes the perceived interference from Congress and has said it would veto such a bill. “If Congress kills this deal, not based on expert analysis, and without offering any reasonable alternative, then it’s the United States that will be blamed for the failure of diplomacy, international unity will collapse, and the path to conflict will widen,” Obama said.

Other lawmakers appear willing to hear out the administration when the negotiators reconvene on April 13, albeit with a heavy dose of skepticism:

What do the Iranians Say?

In Iran, people took to the streets to celebrate news of the framework agreement. In a sign that the deal has the support of supreme leader Ayatollah Khamenei, Friday prayer leaders throughout the country praised the negotiations, calling the talks a success. President Hassan Rouhani, who has spearheaded the talks since he took office in 2013, was scheduled to speak Friday afternoon.

What happens now?

Now the hard work begins, as both sides determine the details and logistics of a deal. The White House will have to contend with a skeptical Congress that wants more of a say in the details of a final deal, as well as with potential schisms with its negotiating partners, which include rival Russia. Meanwhile, the talks will continue even as Iran engages in proxy and increasingly overt wars with U.S. Sunni allies in the region. There’s always the chance that the June 30 deadline will be extended, but as TIME’s Massimo Calabresi notes, “keeping Congress onside, the sanctions coalition together and the Iranians at the table may be impossible after the next deadline.”