Asadollah Asgaroladi urged on Sunday that Kazakhstan and Turkmenistan join the trade interaction among Iran, Russia and Azerbaijan.
He said he has made a suggestion to President Hassan Rouhani for the expansion of Tehran-Moscow-Baku trilateral relations to pan-Caspian ties, saying it would promote economic and trade activities in the Caspian region.
A shift from trilateral relations to five-party interaction among Caspian littoral states would enhance political, economic and cultural cooperation in the region, he said.
On Wednesday, the presidents of Iran, Russia and Azerbaijan held a summit in Tehran to discuss the latest regional developments and mutual cooperation.
Iranian officials has always supported expansion of economic cooperation among the Caspian Sea littoral states -Iran, Russia, Azerbaijan, Kazakhstan and Turkmenistan.
The Caspian Sea is the largest enclosed water body on earth by area, variously classed as the world’s largest lake or a full-fledged sea.