The Days After a Deal with Iran

The president has extensive authority under the law to provide sanctions relief to Iran as part of a comprehensive nuclear agreement. Nevertheless, Congress can take a range of steps to facilitate, hinder, or even block the executive branch's efforts to relieve economic sanctions. It is therefore important to understand Congress' options for shaping the implementation of a nuclear agreement with Iran and to assess the likelihood and impacts of each. On one end of the spectrum of options available to Congress, lawmakers could support a deal's implementation by removing statutory sanctions; on the other, it could withhold funds needed to execute the deal or nullify it through legislation. However, Congress is most likely to take a middle-of-the-road approach that enables the administration to provide sufficient sanctions relief to appeal to Tehran. This approach could involve taking no legislative action at all, which would enable the deal to be implemented as agreed; imposing limits on the president's authority to waive or suspend statutory sanctions; or passing new sanctions designed to punish Iranian non-compliance. In the wake of a diplomatic agreement that includes promises of sanctions relief, new U.S. sanctions would likely scuttle the deal, drive Iran to resume high-level enrichment, undermine global support for sanctions, and leave the United States internationally isolated. As a result, any new sanctions imposed by Congress will likely take effect only if Iran is found to have reneged on its commitments under a deal.