And:

HOUSE CANDIDATE HANDEL ON IRAN DEAL CASH USED FOR SUPPORT OF TERRORISM

 Quote:
In August 2016, many news organizations reported the delivery of $400 million of that $1.7 billion in cash. As part of that exchange, an unmarked cargo plane delivered the money after American officials were certain that three Americans held in Iran were on their way home.

It is not known how the remaining $1.3 billion made its way to Iran. Given the isolation of Iran’s banking system, it is possible that the payment was made in cash and flown to Iran, but neither we nor Handel’s staff could point to any report that said that definitely took place.


and

 Quote:
The idea that the Obama administration admitted that the money is being spent on terrorists comes from something then-Secretary of State John Kerry said in an interview.

Kerry told CNBC’s Squawk Box in January 2016 that Iran could spend the unfrozen assets however it wanted.

"I think that some of it will end up in the hands of the IRGC (Islamic Revolutionary Guards Corps) or of other entities, some of which are labeled terrorists," Kerry said. "To some degree, I’m not going to sit here and tell you that every component of that can be prevented."

The IRGC, as Iran’s premier security institution, fields an army, navy and air force and "presides over a vast power structure with influence over almost every aspect of Iranian life," according to the Council on Foreign Relations think tank. In 2007, the U.S. Treasury Department designated the IRGC’s elite Quds Force a terrorist supporter for aiding the Taliban and other terrorist organizations.


Politifact through odd context rates the statements as "half true".

But an honest evaluation of these facts is that they are 100% true. Cash was given to an Iranian regime that both sponsors terrorism worldwide, and wages terrorism domestically on its own people. And Obama and Kerry gave them $1.7 billion, which Kerry plainly said he agreed to, that if likely would be spent on terrorism.

And despite Politifact's spin. It was not owed to Iran, it was owed to the Iranian government under the Shah that the Islamic regime violently overthrew. That debt was null and void when the Shah was overthrown. If the U.S. wanted to honor that debt, it has been owed for 39 years, and they could choose to pay it at any point when Iran has given up its terrorism and its nuclear ambitions.
Iran never has.
And the fact that Obama and Kerry did not disclose this $1.7 billion payment to the Senate, House or the American voters makes clear how dishonest the deal truly was.

Since neither the House or Senate were given the Constitutional requirement to verify the Iran Deal, it was never truly valid, and Trump has every right to end it.