The story: Russian top presidential aide Igor Levitin has visited Iran for the second time this year. Levitin was hosted by senior officials in Tehran, including Supreme National Security Council (SNSC) Secretary Ali Shamkhani and First Vice President Mohammad Mokhber.

While Iran and Russia's growing military cooperation has been making headlines, the top Russian official’s most recent trip to Tehran appears to have focused on the economic partnership and transit links.

The coverage: Levitin, who also serves as State Council secretary, landed in the Iranian capital late on Apr. 7. He met Mokhber the next day, for the fifth time in the past six months.

• Ahead of Levitin's meeting with Mokhber, Russia's state-run Sputnik news agency said his talks in Tehran would revolve around the International North-South Transport Corridor (INSTC). The initiative seeks to...