With the July 20 deadline for expiration of the interim nuclear agreement with Iran fast approaching, senior and former US officials have given mixed signals about whether the interim deal will have to be extended. But there are compelling reasons to reach a deal before the end of this year that have to do with both domestic politics and bureaucratic considerations. Among them:

• An informed source has told Al-Monitor that Wendy Sherman, the undersecretary of state for political affairs who currently heads the US negotiating delegation in Vienna, will be nominated to replace Deputy Secretary of State Bill Burns. Burns, who also led back channel talks with Iran, is retiring in October. The Barack Obama administration, the source said, would like Sherman to conclude the Iran negotiations before promoting her. An administration official responded to a query from Al-Monitor by saying that Secretary of State John Kerry has not yet made a decision about who will replace Burns.
• Catherine Ashton, the European Union’s high representative for foreign affairs, will be stepping down by the end of the year at the conclusion of a five-year term. Her team, which has been negotiating with the Iranians since talks resumed in 2011, will also leave office. Ashton and her subordinates have earned the trust of both the US and the Iranians and it would be difficult to bring a new team up to speed quickly to conclude these complex talks.
• US congressional elections in November could result in Republicans taking over both houses of Congress next year. This argues for a deal sooner so that the administration can begin to implement the agreement with less likelihood of congressional interference, including possible steps to impose new sanctions on Iran.
• Iranian President Hassan Rouhani will mark the anniversary of his cabinet’s first year in office at the end of August. He could be weakened and domestic political foes emboldened by a failure to deliver on campaign promises to revive the economy, which relies in large part on getting sanctions relief.

As the countdown to July 20 continues, some have argued that at least a limited extension of the interim agreement would do no harm given the constraints placed on Iran’s nuclear program, including suspension of enrichment to 20% U-235 and the conversion of Iran's stockpile of 20% uranium to less proliferation-prone form. Also, sanctions relief given to Iran so far has been minimal.

“All the leverage is with the West because the bulk of the sanctions remain in place,” was how former National Security Adviser Tom Donilon put it Monday at a conference at the Center for Strategic and International Studies in Washington that dwelt on the success of US-led sanctions and financial intelligence.

As Al-Monitor wrote in the Week in Review on May 23, “The International Atomic Energy Agency documents a seriousness of commitment by Iran since the interim agreement began implementation in January. In a report released on May 23, the IAEA notes that 'Iran has implemented the seven practical measures that it agreed with the Agency in February 2014 in relation to the Framework for Cooperation'; 'Iran has not enriched' uranium above 5% 'at any of its declared facilities'; Iran’s stock of uranium enriched up to 20% 'has decreased from 209.1 kg to 38.4 kg'; and 'all of the enrichment related activities at Iran’s declared facilities are under agency safeguards, and all of the nuclear material, installed cascades, and feed and withdrawal stations at those facilities are subject to Agency containment and surveillance.'”