South Korea plans to dispatch a special envoy to Iran as it intensifies efforts to ensure safe passage for dozens of its vessels stranded in the Strait of Hormuz.

The closure of the strait has choked off around 70 percent of the S.Korea's crude oil imports and stranded 26 ships.

On Thursday, South Korean Foreign Minister Cho Hyun held a phone call with his Iranian counterpart, Abbas Araghchi, the second in three weeks, in which Araghchi welcomed Cho's decision to send a special envoy and agreed to continue communication on related matters.