Recently, there was talk that Russia could sell C-400 "Triumph" to Iran, but Vladimir Kozhin said that we are still talking about C-300. RIA News quotes the assistant to the Russian president:
This will be the C-300 complex that Iran wanted to receive. A lot of time has passed, it was partially refined, individual elements are being finalized.

Meanwhile, in the United States, the scandal around the decision of the current presidential administration is beginning to grow in order to begin a phased lifting of sanctions against Iran. Republicans say they are ready to block the decision of Obama. The issue of Iran’s nuclear program is already being exploited by US presidential candidates (in particular, Jeb Bush).