In a public statement, Obama said the Joint Comprehensive Plan of Action (JCPOA) with Iran, which he signed in 2015 is working.
“The reality is clear,” he wrote. “The JCPOA is working – that is a view shared by our European allies, independent experts, and the current U.S. Secretary of Defense.”
Obama praised the deal as a “model for what diplomacy can accomplish,” and said that it has prevented Iran from developing its nuclear program.
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The multi-country deal required Iran to curb its nuclear program, and in exchange, lifted some sanctions on Tehran that had previously hindered its economy.
But U.S. President Donald Trump said Tuesday the deal has done the opposite, and allowed Iran to expand its nuclear capabilities.
“This was a one-sided deal that should have never, ever been made,” Trump said during an address at the White House.
He added that the U.S. will begin reinstating sanctions on Iran in the coming months.
Obama called the decision “misguided,” explaining that Trump has turned his back on U.S. allies that are still part of the deal. Trump has also put America’s credibility at risk by “flouting” agreements, he said.
The former president urged Trump to make decisions based on facts — and pointed a few out.
WATCH: Iran president warns of ‘problems’ as Trump exits Iran deal
Obama noted that the JCPOA has been embraced by many ally countries, as well as the United Nations.
He added that Iran has actually destroyed the core of a reactor that could have produced weapons, placed thousands of centrifuges under international monitoring and eliminated most of its uranium stockpile.
U.S. intelligence and the International Atomic Energy Agency both agree that Iran is complying with the deal, Obama said.
“Our ability to confront Iran’s destabilizing behavior – and to sustain a unity of purpose with our allies – is strengthened with the JCPOA, and weakened without it,” he wrote.
The former president added that he hopes Americans will speak out in support of the deal, and the U.S. will ultimately decide to uphold its global responsibilities.
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“In a dangerous world, America must be able to rely in part on strong, principled diplomacy to secure our country.”
Obama isn’t the only prominent figure expressing concern over Trump’s decision to withdraw from the nuclear deal.
In a joint statement, French, British and German officials urged all remaining parties to remain in the deal.
“We urge the U.S. to ensure that the structures of the JCPOA (deal) can remain intact, and to avoid taking action which obstructs its full implementation by all other parties to the deal,” the statement provided by Prime Minister Theresa May’s office read.
Russia’s foreign ministry also said it is “deeply disappointed” by the decision.