In a message on Saturday, Hossein Amirabdollahian offered his condolences to the Kuwaiti nation and government on the loss of the emir.
He also wished success, dignity and security for Kuwait.
The emir of Kuwait died at 86 on Saturday.
Authorities gave no cause of death, but announced the start of a 40-day official mourning period and a three-day closure of government departments.
Kuwait’s crown prince and his half-brother, Sheikh Meshaal al-Ahmad al-Jaber al-Sabah, 83, was subsequently named new emir.