DUBAI — A wave of optimism has swept Iran since Hassan Rohani was elected president last month, but as he takes office Sunday the moderate cleric has a monumental task to resolve the nuclear dispute, ease stringent sanctions and revive a failing economy. If that were not enough, he has to do this while trying to satisfy the demands of his reformist allies while outflanking the conservatives he defeated, but who still dominate parliament and are deeply embedded within the state. But no matter what progress, if any, Rohani makes towards resolving Iran's myriad problems, President Mahmoud Ahmadinejad's eight years in office are at an end, to the relief of his critics at home and abroad. Ahmadinejad's abrasive rhetoric and unwillingness to compromise precluded any nuclear deal with the West while ever tightening sanctions, domestic mismanagement and misguided state handouts sent inflation soaring over 40 percent, increasing the suffering of many ordinary Iranians.“Before the election, everyone was saying anyone, anyone at all, has to be better than Ahmadinejad,” said one Tehran resident. “Now people hope Rohani might be able to change things, at least a bit.” Similar optimism has greeted Rohani abroad where he has pledged to pursue a less confrontational approach to Iran's talks with six world powers over a nuclear program the West suspects is a veiled attempt to achieve a nuclear weapons capability. Iran says its efforts are entirely peaceful. “The historic election of Hassan Rohani last month in Iran was widely seen as a rejection of radicalism and an embrace of moderation. Hopes have risen that a negotiated solution to the nuclear stand-off may now be within reach,” said Trita Parsi, president of the National Iranian American Council. Rohani is however very much an Islamic Republic insider with 16 years as head of the Supreme National Security Council and the last eight years as one of two personal representatives of Supreme Leader Ayatollah Ali Khamenei on the same body. Even so, Rohani has still been making all the right noises. “Of course our nuclear plans are fully transparent, but we are ready to show more transparency,” said Rohani, setting out his stall at his first post-election news conference. “Second, we will increase mutual trust between Iran and other countries.” “Mutual trust and transparency within the framework of international regulations and principles are the solution to end sanctions,” he said. “We will first have to prevent new sanctions being applied, then reduce them and later, God willing, to completely remove them.” Such words however failed to move the US House of Representatives which easily passed a bill this week to tighten sanctions on Iran, further cutting its oil exports despite warnings from White House officials who said they wanted to give Rohani a chance. Rouhani may take some comfort from the reaction of one of the six powers, Russia, which said the US move would not resolve the dispute over Iran's nuclear program. Rohani has also made conciliatory noises about Syria where Iran has provided military training and credit to help President Bashar Al-Assad in his more than two-year battle to defeat insurgents supported by Gulf Arab and some Western states. Praising the Syrian government for standing up to what he called “Israeli expansionist policies and practices”, Rohani has offered to mediate between Assad “and those in the opposition who strive for democracy and good governance”. The president however has little control over the activities abroad of the Revolutionary Guards who report directly to the leader and have their own independent sources of funds. Though Khamenei, the top man in Iran's complex power structure, calls all the shots when it comes to nuclear and security issues, the president is given a relatively free hand to run the economy, and that is the big issue for Iranians. Of course, much depends on Rouhani's ability to gain some wiggle room from swingeing United Nations, US and EU sanctions that have helped fuel inflation and halved the value of the rial in the last 18 months. — Reuters