When Joe Biden came to office the Iran Nuclear Dead was on life support.

Known formally as the Joint Comprehensive Plan of Action, or JCPOA, the Obama-era deal lifted US and UN  sanctions on Iran in return for Iran placing verifiable limits on its nuclear program.

The deal was rejected by the Trump administration which re-imposed sanctions; and Iran has responded in kind by re-starting certain aspects of its nuclear program.

Here to explain where things stand with nuclear diplomacy between the United States and Iran is Kelsey Davenport, director for non-proliferation policy policy at the Arms Control Association. We spoke ahead of planned talks in Vienna between the United States and Iran, scheduled for the end of November and early December.