WASHINGTON — When Undersecretary of State Wendy Sherman addressed a roomful of 200 foreign ambassadors to the United States last week, she implored them to tell their capitals to pass two crucial messages to the Iranians: the importance of seizing what may be the last opportunity to reach a nuclear deal, and that no agreement will be possible without Iran reducing the scope of its nuclear enrichment program.

“Ambassador Sherman’s remarks on Iran were focused on the importance of seizing this opportunity to resolve international concerns about Iran's nuclear program, and the fact that no agreement — and no relief from sanctions — will be possible unless Iran agrees to reduce — significantly and verifiably — the size of its uranium enrichment activities,” a senior US administration official familiar with Sherman’s briefing told Al-Monitor.

Sherman’s message on Iran at the briefing to Washington’s diplomatic corps comes ahead of what is expected to be an intense and frenetic diplomatic drama as nuclear negotiations between Iran and six world powers (China, France, Russia, the United Kingdom and the United States plus Germany, or P5+1) resume in New York this week, alongside events marking the opening session of the UN General Assembly (UNGA). 

Amid the UN-related hoopla and drama — will President Barack Obama and Iranian President Hassan Rouhani follow up their phone call last year with a meeting? a handshake? — the nuclear negotiations are picking up with renewed urgency after an August lull in which little progress was made in closing the major obstacles to a nuclear deal, diplomatic sources tell Al-Monitor.