As Iran and the United Nations nuclear watchdog, the International Atomic Energy Agency (IAEA), meet in Vienna today for a new round of talks over the country’s controversial nuclear program, the P-5+1 (the U.S., Britain, France, Russia, China plus Germany) are watching closely ahead of their own talks with Iran in Moscow on June 18.

Council on Foreign Relations senior fellow Michael A. Levi highlights three things to know about today’s Iran-IAEA negotiations:

Iran’s Parchin Military Complex: Will Iran provide nuclear inspectors with access to the military site where some evidence suggests it’s a site for development of parts for a nuclear weapon? “Iran has stalled for several months on access to the site,” says Levi. “The IAEA would still like to go there, and there will still be controversy over it.”

Iran’s continuing and increased level of uranium enrichment: “The focus of broader diplomacy in particular is on this higher-level enrichment and this enrichment that might be beyond the reach of Western military strikes,” he says.

P-5+1 negotiations: The result of today’s negotiations between Iran and the IAEA will play into talks June 18-19 between Iran and the P-5+1 in how they “position themselves to take advantage of whatever outcome there is to the Iran-IAEA talks,” says Levi. Last month’s talks in Baghdad began with optimism but ended with disappointment and no sign of starting points the next round of talks.