President Barack Obama is trying to negotiate a nuclear deal with Iran. But the President and Democratic politicians are upset about an open letter from 47 GOP U.S. senators to Iranian leadership. The letter claimed the senators:

    "Will consider any agreement regarding your nuclear-weapons program that is not approved by the Congress as nothing more than an executive agreement between President Obama and Ayatollah Khamenei. The next president could revoke such an executive agreement with the stroke of a pen and future Congresses could modify the terms of the agreement at any time."

PolitiFact rated the claim for its truthfulness. Writer Joshua Gillin said the claim rates MOSTLY TRUE. According to Gillin, the letter oversimplifies a complicated matter.

“There's a difference between a treaty and an executive agreement,” Gillin said. “And about 95 percent of diplomacy through the White House is an executive agreement.”

There’s not much in the U.S. Constitution about executive agreements. The practice was rubber stamped by the U.S. Supreme Court in three different cases.

Executive agreements are easier to negotiate since they don’t require Congressional approval. However, that also makes them easier to reverse.

Experts say it’s clear that a future president could undo executive agreements. And Congress does have the authority to pass laws that would supersede an executive agreement.

In the case of Iran, any potential deal would likely include some kind of Congressional role. Any permanent deal would most likely require congressional action.

In addition, in this specific case, doesn’t seem that Congress would be able to modify an agreement anytime. This agreement is being negotiated between the five permanent United Nations Security Council members, as well as Germany. For the agreement to truly be changed, the other countries would also have to sign off.

Because the letter is mostly accurate, but tends to exaggerate the ease in which an agreement could be modified, PolitiFact rated the claim MOSTLY TRUE.

SOURCES: GOP LETTER TO IRAN