Oath of office: Iran's new President Hassan Rohani pledged to shun extremism and take a moderate approach.

Oath of office: Iran's new President Hassan Rohani pledged to shun extremism and take a moderate approach. Photo: AFP

Tehran: Iran's new President, Hassan Rohani, was set to take the oath before parliament on Sunday, a day after taking office with a promise to work to ease crippling Western sanctions.

The 64-year-old cleric, who the West is hoping will take a more constructive approach in long-running negotiations over Iran's controversial nuclear program, was also expected to unveil his government line-up, Iranian media reported.

Mr Rohani formally took office on Saturday at a ceremony in which he received the endorsement of supreme leader Ayatollah Ali Khamenei, who retains the final say on all strategic issues, including the nuclear talks.

Ten leaders from around the region, including the Prime Minister of close ally Syria, were due to attend Sunday's parliamentary session, Iranian reports said.

Also present was former European Union foreign policy chief Javier Solana, who has represented world powers in nuclear talks with Tehran in the past.

Mr Rohani begins his four-year term with Iran facing international isolation and tough EU and US sanctions against its oil and banking sectors that have sent the value of the rial plummeting and inflation soaring.

The moderate conservative, who is himself a former chief nuclear negotiator, has vowed to engage more constructively with the international community in a bid to reverse the damage caused by the hardline policies of his firebrand predecessor, Mahmoud Ahmadinejad.

His first staff appointment, the nomination as chief of staff of Chamber of Commerce and Industry president Mohammad Nahavandian, who holds a doctorate in economics from George Washington University and a US Green Card, was seen as a statement of his priorities.

"The trajectory of my government will be saving Iran's economy and constructive engagement with the world," Mr Rohani said in a speech on Saturday broadcast live on state television.

His government would "take fundamental steps in elevating Iran's position based on national interest and lifting of the oppressive sanctions", he said.

The crippling EU and US sanctions, imposed over and above the United Nations sanctions slapped on Iran over its refusal to suspend uranium enrichment, have dealt a heavy blow to Iran's economy.

Over the past two years the sanctions have sent inflation soaring to more than 45 per cent, while the rial lost nearly 70 per cent of its value against the US dollar and created double-digit unemployment.

Western governments suspect that Iran's nuclear program is cover for a drive for a weapons capability. Iran insists it is for power generation and medical purposes only.

Both the US and Israel – which has the Middle East's sole, if undeclared, nuclear arsenal – have refused to rule out a resort to military action to prevent Iran developing a weapons capability.

Israeli Prime Minister Benjamin Netanyahu charged on Sunday that Mr Rohani shared his hardline predecessor's aim of destroying the Jewish state.

"The president of Iran may have been changed but the aims of the regime there have not," he said at the start of a weekly cabinet meeting.

Mr Rohani scored a surprise first-round presidential election victory over five conservatives on June 14, on a pledge to resolve tensions with the major powers and revive Iran's economy.

Iran has held repeated rounds of talks with the so-called P5+1 group of Britain, China, France, Russia and the US plus Germany, but they have failed to allay Western concerns.

Mr Solana, who represented the P5+1 in past talks with Iran, was in Tehran for Sunday's swearing-in.

In an interview published by Iran's reformist Shargh newspaper on Sunday, the former EU foreign policy chief called Mr Rohani "a politician with insight . . . with whom one can strike a deal".

Ahead of the swearing-in, Mr Rohani held talks with Syrian Prime Minister Wael al-Halqi and promised there would be no change in the two governments' close alliance, Syrian state media reported.

"No force in the world can shake the solid, strategic and historic relations that bind the two countries in friendship," he was quoted as saying.

Iran has been the main regional ally of President Bashar al-Assad's regime in its efforts to defeat a 28-month-old uprising against his rule.

Officially Mr Rohani has two weeks from Sunday to name his cabinet, and the conservative-dominated parliament then has 10 days to review his nominations.

But Iranian media said he could unveil his cabinet on Sunday and MPs start the confirmation process within a week.

They reported that he was likely to name a government dominated by Western-educated technocrats like Mr Nahavandian.

AFP