TEHRAN - Richard Nephew, who was a top negotiator with Iran over the country nuclear program up until late 2014, says that how the implementation of the nuclear deal in the long-term will be influenced by the U.S. presidential election will “depend greatly on who wins the election.”  

“In the short-term, there will be no impact, as the Obama Administration remains in office and the President himself has underscored his support for the JCPOA,” Nephew tells the Tehran Times.
Former Principal Deputy Coordinator for Sanctions Policy at the Department of State says that “if the likely Republican nominee - Donald Trump - becomes president, then it is possible the JCPOA will no longer exist when he enters office in January 2017.”
Following is the full text of the interview with Richard Nephew:
Q: What will be the impact of the U.S. presidential election on the implementation of the Joint Comprehensive Plan of Action (JCPOA)?
A: The long-term impact will depend greatly on who wins the election.  In the short-term, there will be no impact, as the Obama Administration remains in office and the President himself has underscored his support for the JCPOA.
Q: Do you think there is any difference between Republican or Democrat final nominees when it comes to implementing the JCPA?
A: Not for the near-term.  But, if the likely Republican nominee - Donald Trump - becomes president, then it is possible the JCPOA will no longer exist when he enters office in January 2017.  He has said that he would terminate the deal on his first day in office.  On the other hand, though, he has also said that he intends to be unpredictable and flexible, and that he may change his mind.  Candidly, we may not know what Donald Trump intends to do until he is in office and it may change.  
If either Hillary Clinton or Bernie Sanders were to be president, then I believe they would both continue to support the implementation of the JCPOA so long as there are no indications of Iran’s lack of commitment.  If there were to be indications of this, then I would expect to seek to address any violations within the terms of the deal, using the dispute resolution process that the JCPOA established.
Q: Which candidate will be the better option for Iran? Democrat or Republican one?
A: I think this is probably too difficult to answer without injecting my personal bias.  I believe that Hillary Clinton should be the next U.S. President as she will be best for the United States.  Insofar as Iran is concerned, she has made not only her concerns with Iranian policy very clear but also her readiness to engage with Iran diplomatically to help address those concerns. I share her concerns and support her approach.