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President Donald Trump said Thursday that Iran is violating the “spirit” of the nuclear agreement it struck with world powers in 2015.

“Iran has not lived up to the spirit of the agreement,” Trump said at the White House during a joint press conference with the Italian prime minister, apparently contradicting what his own State Department said earlier in the week.

“The U.S. Department of State certified to U.S. House Speaker Paul Ryan today that Iran is compliant through April 18th with its commitments under the Joint Comprehensive Plan of Action,” the department said on Tuesday.

Only hours later, however, Secretary of State Rex Tillerson agreed with Trump and described the landmark deal as a failure.

On "Special Report" tonight, Charles Krauthammer said this is not a flip-flop for the Trump administration.

He explained that an Iranian dissident group is alleging that Iran’s clandestine work on a nuclear weapon has continued after the deal., which he said may not violate the actual text of the deal, but certainly the "spirit."

He said that three things are needed to develop a usable a nuclear weapon: fissile material, a way a to weaponize it, and ballistic missiles.

"The problem is that the Obama administration looked only at the fissile element," Krauthammer said. "But what the Iranians are doing - and this is so obvious a child could see it - is while the program on the fissile material is frozen, they're working rapidly on the weaponization ... and of course on the ballistic missiles, which we can see."

"Yes, they are developing a nuclear weapon. It's a violation of the 'spirit' of agreement, because the way they look at it, in half a decade, they'll be able to resume the fissile material - the enriching uranium - they will have weaponized, and they will have the missiles."

Watch more above.

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