US President Barack Obama delivered a statement on the deal struck between Iran and world powers at 7 a.m. EST (2 p.m. in Israel) from the White House.

"Today, after 2 years of negotiations, the US, together with our international partners, has achieved something that decades of animosity has not: a comprehensive, long-term deal that prevents Iran from obtaining a nuclear weapon," he said. 

Obama stated that the deal fits with a "long tradition of American leadership," quoting John F. Kennedy saying, "let us never negotiate out of fear, but never let us fear to negotiate." 

According to the president, the deal blocks the risk of nuclear arms proliferation in the Middle East.

"Every pathway to nuclear weapons is cut off" for Iran, he added, saying that a monitoring system will be in place. "Because of this deal, Iran will remove 2/3 of its installed centrifuges."

"Iran will not use its advanced centrifuges ... for the next decade," he said, even though the deal reportedly will allow it to continue using the advanced centrifuges for research.

Stockpiles will remain limited by 98% for 15 years, and Iran has agreed to send fuel from the reactor out of the country for the lifetime of the Arak heavy water reactor.

Iran will be prevented from building any heavy water reactors for the next 15 years, he said. 

"The IAEA will have access where necessary, when necessary" to nuclear sites, he said, adding that that access is "permanent."

Regarding this access, he did not note military facilities thought to have been used in developing nuclear weapons such as Parchin, but he said Iran won't be able to transfer nuclear materials to "covert" facilities.

"Finally, Iran is permanently prohibited from producing a nuclear weapon under the Nuclear Non-Proliferation Treaty," Obama said. 

Sanctions relief will be "phased in" and only after the agreement is implemented, he said. Iran must prove that it has followed the deal for 5 years before the UN conventional arms embargo is lifted, and 8 years before it can produce ballistic missiles.

Obama added that sanctions will snap back if the deal is broken. 

"I will veto Congress"

"Consider what happens in a world without this deal," he argued. "Without this deal, there would be no agreed-upon limitations for the Iranian nuclear program." 

He claimed that without a nuclear deal the world wouldn't "join us" in pressuring Iran, and wouldn't "sanction Iran into submission."

Not having a deal makes a regional nuclear arms race "more likely," claimed Obama, because it would lead to less oversight in Iran.

He noted that during his time in office he has weighed whether to use military force or not in several countries, and he "will not hesitate to do so if need be for our national security interests."

The Iran deal, however, precludes a threat to those interests, he said. "Simply: no deal means a greater chance of more war in the Middle East." 

"I strongly believe that our national security interest now depends upon preventing Iran from obtaining a nuclear weapon, which means that without a diplomatic resolution either I or a future US president would face a decision" to military confront Iran, he said.

If Iran violates the deal, a future US president will have the same options "available to me today," and in 15 years from now a new president will be in a "stronger position" to confront Iran's program, he added.

"For this reason, I believe it will be irresponsible to walk away from this deal," he said. However, he qualified that the American people and their representatives in Congress deserve the right to debate the issue in Congress.

"I welcome scrutiny of details in this agreement," he said. "But I remind Congress: you don't make deals like this with your friends." 

"I will veto any legislation that prevents the successful implementation of this deal," he warned. "This is not the time for politics or posturing. ...Tough talk from Washington does not solve problems."

"We support Israel"

Obama then addressed the opposition to the deal from Israel and the Gulf states, arguing that a world without an Iran deal would provide a greater threat to the region and the world.

"We will continue our unprecedented efforts to strengthen Israel's security, efforts beyond what any administration has done before," he claimed. 

"It is possible to change," he said of Iran's threats to "eradicate Israel," and called for a "different path" of "tolerance" from the Islamic regime, which is the leading state sponsor of terror.

"We must continue to test whether this region, which has known so much suffering, so much bloodshed, can move in a different direction." 

He noted to the Iranian people that extremism and calls of 'Death to Israel' are a "dead end," in his words, saying that "this is an opportunity, and we should seize it." 

Thanking US Secretary of State John Kerry, he noted that four decades ago he "put on our uniform and went off to war," and now he is making America "safe" with his diplomacy.

"History shows that America must lead not just with our might, but with our principles," he concluded, saying that the deal will lead to "a safer, more hopeful world." 

Earlier Tuesday, a selection of foreign ministers involved in the talks, from both Iran and the West, announced a "win-win" deal had been reached vis-a-vis Iran's nuclear program.

However, it remained unclear what the exact terms of the deal were, and all sides are due to update the public Tuesday afternoon.

Early preliminary reports from the talks have emerged showing two distinctly different terms for the deal; while one Iranian diplomat presented to Reuters terms suggesting a deal tempered by demands from the West, Iranian state media presented a deal alleging complete concessions from the West on several "red lines." 

Ari Yashar contributed to this report.