Thousands of Iranian hardliners have rallied at the former US embassy in Tehran to commemorate the 1979 US hostage crisis, highlighting the domestic challenges the country's president, Hassan Rouhani, faces in his bid to mend ties with the west.
In a nationwide event marking the anniversary of the day angry students stormed the embassy 34 years ago and took 52 diplomats hostage for 444 days, large crowds sympathetic to the Revolutionary Guards and its informal voluntary basij militia took to the streets on Monday, chanting "death to America" and burning US flags.
Demonstrations have been held annually on the "national day against global arrogance". But this year, with Rouhani's new administration attempting to improve relations with Washington, it became a show of defiance by hardliners adamantly opposed to a thaw in relations.
Many senior officials failed to turn up for Monday's rallies and there was no sign of Rouhani or his cabinet members. Instead, Saeed Jalili, a former nuclear negotiator who ran as the most anti-western candidate and was defeated in the last presidential election, took to the podium in Tehran.
"Death to America means death to arrogance, death to violence … Death to America is a symbol," he reportedly said. "The Iranian people turned it into a symbol for seeking freedom and seeking independence."
Witnesses said that demonstrators appeared to be part of organised groups bussed in by the guards or the basij.
Hundreds of students from various schools and universities in the Iranian capital were also given a day off to attend the rallies. Some were carrying cardboard models of a uranium enrichment centrifuge. "America can't do a damn thing," said a banner, which is a famous quote by the late founder of the Islamic republic, Ayatollah Ruhollah Khomeini.
A Tehran-based journalist allowed to cover the demonstrations for the American network NBC tweeted a picture of his official press card issued by the Iranian officials, which had "Down with USA" printed on it.
Many of the students who played a key role in the 1979 embassy takeover have become reformists and have been largely marginalised, including Ebrahim Asgharzadeh, Habibollah Bitaraf and Mohsen Mirdamadi, who was jailed in 2009.
Before Monday's rallies, Asgharzadeh, one of the five key students behind the hostage-taking, told local website Ghanoon they intended to occupy the embassy for no more than 48 hours but lost control. "We only wanted to stage a sit-in protest and did not anticipate such resistance from them; we did not intend to take anyone hostage," he said. "But [later] we became hostages ourselves of this hostage-taking." To the dismay of Iranian authorities, the hostage crisis became the subject of the Oscar-winning Argo, a 2012 thriller by Ben Affleck. Iran has since promised to retaliate by producing its own version of the events.
In his speech, Jalili said the seizure of "the nest of spies", a reference to the former US embassy, showed to the world that American embassies were a base for spying. The ex-embassy's compound, situated in central Tehran, has been transformed into a museum run by the basij which exhibits some of the documents and belongings confiscated in 1979.
Despite his anti-US rhetoric, Jalili said Iranians are united behind their negotiators.
Iran's supreme leader, Ayatollah Ali Khamenei, also made a speech on Sunday in which he said he was not optimistic about the ongoing negotiations with the west over Tehran's nuclear programme. But he voiced strong support for Rouhani's diplomacy.
"No one should consider our negotiators as compromisers," he said. "They have a difficult mission and no one must weaken an official who is busy with work." Iran and the six major powers – Britain, China, France, Russia, the US and Germany – are due to resume nuclear talks in Geneva later this week within a month of holding a similar event in October.
In his speech, without naming Edward Snowden and his revelations, Khamenei also alluded to the furore over the scale of US intelligence surveillance.
"On that day, our youths named the US embassy the 'den of espionage' and today, after over three decades, US embassies in the European countries, which are American allies, are called nests of espionage," said Khamenei. "This shows that our youths were over 30 years ahead of the world calendar."
Rouhani issued a statement on Sunday night thanking Khamenei for his support for the negotiating team and said Iran was not at odds with the American people.
In September, Rouhani travelled to New York for the UN general assembly, launching a largely successful charm offensive.
That visit featured a historic phone conversation between Rouhani and Barack Obama, the first direct talks between US and Iranian presidents since the 1979 Islamic revolution.
But the backlash from the visit is still creating ripples at home, where anti-US sentiment is the very bedrock of the Islamic republic's ideology for many of its conservatives and fundamentalists.
After Rouhani's return from New York, a debate began to grow on whether the authorities should officially drop the "death to America" slogans, but opposition from hardliners mean they will not disappear any time soon.
Last month, Tehran citizens noticed a series of billboards in streets showing an Iranian negotiator talking face to face behind a table to his American counterpart, pictured as a half-civilian, half-military man with a pump-action shotgun in his lap.
Opponents of the billboards said they were installed to undermine Rouhani's diplomacy with Washington, which led to Tehran city officials taking them off the streets. The billboards have since returned, highlighting the top-level internal disagreements in Iran.
Meanwhile, early on Monday, as demonstrators prepared for the anti-American rallies, judicial authorities executed Sherko Moarefi, an Iranian Kurdish activist who had been in jail since 2008 – despite a long campaign by human rights activists calling on Iran to halt his death sentence, saying he did not get a fair trial..