Iran's Supreme Leader Ali Khamenei confirmed First Vice President Mohammad Mokhber as interim head of the country's executive branch following the death of President Ebrahim Raisi in a helicopter crash.

Raisi, Foreign Minister Hossein Amir-Abdollahian and other officials were confirmed dead on Monday after the helicopter they were in crashed into a mountainous region in northwest Iran, according to state TV.

The officials were traveling in Iran's East Azerbaijan province when the helicopter made what was described as a "hard landing" by Iranian media. The governor of the East Azerbaijan province and other officials and bodyguards were also aboard, according to the state-run IRNA news agency.

IRAN'S PRESIDENT, FOREIGN MINISTER, OTHER OFFICIALS CONFIRMED DEAD IN HELICOPTER CRASH

Mokhber "will manage the executive branch and is obliged to arrange with the heads of the legislative and judicial branches to elect a new president within a maximum of 50 days," according to the supreme leader.

Khamenei, who has the last say in all matters of state, also announced five days of public mourning following Raisi's unexpected death.

"I announce five days of public mourning and offer my condolences to the dear people of Iran," he said in a statement published by IRNA.

IRANIAN PRESIDENT EXPERIENCES 'HARD LANDING' IN HELICOPTER: IRANIAN MEDIA

Iran now has a maximum of 50 days to hold a presidential election to select Raisi's successor.

Article 131 of Iran's constitution states that a council of the first vice president, the speaker of parliament and the head of the judiciary must prepare for the election of a new president.

Mokhber became first vice president in 2021 when Raisi was elected president.

Reuters contributed to this report.