The re-election of Iranian President Hassan Rouhani is unlikely to change the skepticism with which he is viewed by the Trump administration as the public face of a government opposed to US interests and allies in the Middle East, former US officials and analysts say.
Mr Rouhani, a cleric who, with Foreign Minister Javad Zarif, broke the taboo of holding direct talks with the United States and reached an international deal in 2015 to curb Iran's nuclear program in return for relief from economic sanctions, won 57 percent of the vote in Friday's election.
US President Donald Trump's administration seems likely to want to keep putting pressure on Iran over its weapons programs and what it sees as Tehran's destabilising efforts in the Middle East, analysts said.
"I think the Trump administration will remain pretty consistent on this issue. So I don't expect any change" in policy toward Iran, said Reuel Marc Gerecht, a senior fellow at the conservative Foundation for Defense of Democracy, and a former CIA Iran specialist.
Despite the nuclear deal, the United States still considers Iran a "state sponsor of terrorism".
There was no immediate reaction to Mr Rouhani's victory from the Trump administration. Mr Trump is visiting Iran's main regional rivals, Saudi Arabia and Israel, on his first foreign trip.
While Mr Trump, a Republican, has harshly criticised the nuclear accord struck under predecessor President Barack Obama, a Democrat, he has kept it alive while signalling a desire to confront Iran more directly.
Washington says Tehran's support for Syrian President Bashar al-Assad in Syria's civil war, Houthi rebels in Yemen, and the Hezbollah political party and militia in Lebanon, have helped destabilise the Middle East.
Ahmad Majidyar, an expert with the Washington-based Middle East Institute, forecast growing tensions between the United States and Iran over Iraq and Syria, where US-backed forces and Iran-supported Shiite Muslim militias are fighting Islamic State.
"Washington and Tehran are de facto allies in the fight against Islamic State," Majidyar said. "But now ISIS is on the verge of defeat, we see signs of tensions between Iranian backed- militia forces and the US forces."
Rouhani's promise to Iranians
Mr Rouhani has pledged to open Iran to the world and deliver freedoms its people have yearned for, throwing down a defiant challenge to his hardline opponents after securing a decisive re-election for a second term.
Mr Rouhani, long known as a cautious and mild-mannered establishment insider, reinvented himself as a bold champion of reform during the election campaign, which culminated on Friday in victory with more than 57 percent of the vote. His main challenger, hardline judge Ebrahim Raisi, received 38 percent.
In his first televised speech after the result, Mr Rouhani appeared to openly defy conservative judges by praising the spiritual leader of the reform camp, former President Mohammad Khatami. A court has banned quoting or naming Mr Khatami on air.
"Our nation's message in the election was clear: Iran's nation chose the path of interaction with the world, away from violence and extremism," Mr Rouhani said. He promised to serve as president for all Iranians, not just those who voted for him.
Although the powers of the elected president are limited by those of unelected Supreme Leader Ayatollah Ali Khamenei who outranks him, the scale of Mr Rouhani's victory gives the pro-reform camp its strongest mandate in at least 12 years to seek the sort of change that hardliners have thwarted for decades.
"We won. We did what we should do for our country. Now it is Rouhani's turn to keep his promises," said coffee shop owner Arash Geranmayeh, 29, reached by telephone in Tehran.
Mr Rouhani, 68, faces the same limits on his power to transform Iran that prevented him from delivering social change in his first term, and that thwarted Khatami, who failed to deliver on a reform agenda as president from 1997-2005.
But by publicly thanking "my dear brother, Mohammad Khatami" in his victory speech, Mr Rouhani seemed to take up that mantle. It was a remarkable challenge to the Shi'ite Muslim religious judicial authorities, who have blacklisted Mr Khatami from public life for his support for other reformists under house arrest.
Many experts are sceptical that a President can change much in Iran, as long as the supreme leader has veto power over all policies and control over the security forces. Some said the pattern was all too familiar from Mr Rouhani's first victory four years ago and Khatami's victories the previous decade.
"The last two decades of presidential elections have been short days of euphoria followed by long years of disillusionment," said Karim Sadjadpour, senior fellow at the Carnegie Endowment who focuses on Iran.
"Democracy in Iran is allowed to bloom only a few days every four years, while autocracy is evergreen."