Yerkin Delmanov, deputy chairman of the Ak Bidai grain terminal in the Caspian Sea port of Aktau, said 30,000 tons of grain had been loaded for Iran since March 16.
Kazakhstan's relative proximity to Iran has made purchases from the former Soviet republic a viable alternative for private Iranian buyers.
Kazakhstan, struggling with logistical bottlenecks to export a record post-Soviet crop of 27 million tons, expects to ship at least 500,000 tons of grain to Iran in this season, Deputy Agriculture Minister Muslim Umiryayev told Reuters on Wednesday.
That level would at least match last season's shipments to the Islamic republic, which was the biggest taker of Kazakh grain in the 2009-10 marketing year before volumes dropped off last year.
"If since September only barley was being shipped, from the middle of March volumes have been split 50-50 between barley and wheat," Delmanov said.
He said the terminal would maintain this loading ratio until April 15. Thereafter, wheat would account for all remaining grain shipments from the port this season.