On July 29, the lead US Iran negotiator warned lawmakers that congressional action now that would threaten to impose new sanctions on Iran if a final nuclear deal is not reached in November could jeopardize the sensitive negotiations at a critical moment, and unravel the international coalition pursuing them.

“The administration believes quite strongly that at this moment in [the] negotiations, additional legislative action would potentially derail negotiations,” Undersecretary of State Wendy Sherman told the Senate Foreign Relations Committee July 29.

Sherman, testifying with Undersecretary of Treasury David Cohen, also said that any final nuclear deal reached with Iran over the next four months would seek to cut off all pathways for Iran to make a nuclear weapon, or would detect in time any covert efforts to try to do so and prevent them before they occurred.

“What [we are] trying to do [in a final agreement] is cut off every pathway to nuclear weapons,” Sherman said. “This is not about trust or illusions. This is about verification. This is about monitoring. … This is about inspections.”