Two key parts of the Iran nuclear deal will be kept from the prying eyes of Congress.  These "side deals" with Iran involve inspecting a military site long suspected of carrying out nuclear and ballistic missile research and development.

National Review:

Under the terms of the Joint Comprehensive Plan of Action (JCPOA), the International Atomic Energy Agency would negotiate separately with Iran about the inspection of a facility long-suspected of being used to research long-range ballistic missiles and nuclear weapons.

“The Obama administration has failed to make public separate side deals that have been struck for the ‘inspection’ of one of the most important nuclear sites—the Parchin military complex,” said Representative Mike Pompeo (R., Kan.) in a statement Tuesday. “Not only does this violate the Iran Nuclear Agreement Review Act, it is asking Congress to agree to a deal that it cannot review.”

The IAEA has been trying to gain access to the Parchin site since 2005, but Iran has refused, even as it apparently demolished various parts of the complex. “The hardliners do not want to grant any concessions unless Iran is suitably rewarded,” International Institute for Strategic Studies director Mark Fitzpatrick told the BBC in 2014, after reports emerged of explosions at the base.

The terms of the current agreement wouldn’t allow Congress to review any concessions the IAEA makes to get into the site. “Even members of Congress who are sympathetic to this deal cannot and must not accept a deal we aren’t even aware of,” said Pompeo. The IAEA will also separately negotiate “how the IAEA and Iran will resolve outstanding issues on possible military dimensions of Iran’s nuclear program,” according to a release from Pompeo’s office.

Senator Tom Cotton is wondering if there is anything else in the deal the president may be hiding from Congress:

Senator Tom Cotton (R., Ark.) and Pompeo, who serves on the House Intelligence Committee, learned of the arrangement while meeting with the IAEA in Vienna, Austria last week. “That we are only now discovering that parts of this dangerous agreement are being kept secret begs the question of what other elements may also be secret and entirely free from public scrutiny,” Cotton said in a statement to the press.

Under the direction of former IAEA chief Mohamed ElBaradei, the agency was one of Iran's nuclear enablers.  But that changed when Yukiya Amano took over in 2009.  Since then, the IAEA has become much more aggressive in trying to determine Iran's intent and is a lot more skeptical of Iran's claims about the nature of its nuclear program.

But the IAEA will be under tremendous pressure from the big powers to acquiesce to Iranian demands in order to keep the agreement on track.  It makes sense from Obama's point of view to keep Congress in the dark about what concessions the IAEA is making to Iran to get them to sign off on the agreement.  But even Democrats have to acknowledge that keeping these side deals from Congress violates the spirit and probably the letter of the law that gives Congress the right to review the agreement.