TEHRAN - Iran's Supreme Leader Ali Khamenei formally endorsed Masoud Pezeshkian as Iran's ninth president on Sunday.

During a ceremony held in the Iranian capital, Khamenei endorsed a decree issued by Interim President Mohammad Mokhber and handed it over to Pezeshkian, officially approving him as the country's next president.

Pezeshkian was announced as Iran's next president on July 6 following his victory in a runoff against Saeed Jalili, a former chief nuclear negotiator.

Speaking at the ceremony, Iran's leader said Iran successfully passed the "important test" of the 14th presidential election and has done arduous tasks to uphold a healthy and competitive democratic system.

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Khamenei called on the new administration to use Iran's rich natural resources and human resources to do great things, calling for greater unity and cooperation among different pillars of the country, including the administration, judiciary, parliament, and armed forces.

The leader described the resolution of the economic problems as the country's present top priority, calling for increasing the national currency's value and domestic production, attracting investments, and improving the business atmosphere.

He urged for greater reliance on domestic capabilities and the use of international interactions and capacities while warning against tying the fate of domestic problems to foreign issues.

As to the country's foreign policy priorities, he called for strengthening ties with supportive states, improving relations with the neighbors, Asian and African countries, and taking an active approach towards global and regional developments.

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Speaking at the ceremony after receiving his decree, Pezeshkian stressed that serving the country's people should be a priority and high on the agenda of his administration.

He added that the Iranian people, by voting in favor of a "change", had assigned a heavy responsibility to him, which had practically begun as of "today".

Pezeshkian reaffirmed his commitment to implement general policies introduced by the supreme leader and realize goals set by the country's Islamic establishment and the seventh cultural, social, and economic development plan.

He highlighted the necessity to achieve national unity and promote a law-abiding society.

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Following the endorsement, a sworn-in ceremony was scheduled for the new president on Tuesday.

New first vice-president

Pezeshkian on Sunday also appointed Mohammad-Reza Aref as his first vice-president, the official news agency IRNA reported.

Article 124 of Iran's Constitution stipulates that "the president may have vice-presidents for the performance of his constitutional duties and with the president's approval, the first vice-president shall be responsible for handling the cabinet's affairs and ensuring coordination among the other vice presidencies."

In a decree, Pezeshkian called on Aref to, among other things, run the cabinet meetings, ensure coordination among ministers and the country's other executive officials, and be in charge of communicating the cabinet's approvals.

A current member of Iran's Expediency Discernment Council, Aref, a reformist politician born in December 1951, served as Iran's first vice-president from 2001 to 2005 under former president Mohammad Khatami.

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He served as the head of the Ministry of Post, Telegraph and Telephone, currently known as the Ministry of Information and Communication Technology, from 1997 to 2000 and was appointed as the head of the country's Management and Planning Organization in the same year during Khatami's first four-year term.

He also served as a lawmaker in the 10th Iranian parliament. Aref has a PhD in electrical and communication engineering from Stanford University.

Aref ran for president in 2013 but dropped out of the race in favor of Hassan Rouhani, who was elected president for two consecutive terms.

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Pezeshkian was announced as Iran's next president on July 6 following his victory in a runoff against Saeed Jalili, a former chief nuclear negotiator.

His swearing-in ceremony will be held at Iran's parliament in Tehran on Tuesday afternoon. After his endorsement by the leader, Pezeshkian took over the presidential office from Interim President Mohammad Mokhber.