While U.S. and Iranian negotiators gave themselves more time Friday to reach a nuclear deal that could improve the countries' ties, crowds of Iranians here chanted "Death to America," just as they have for 36 years.
The occasion was Quds Day, an annual holiday observed since the Iranian revolution to express support for the Palestinians in their struggle with Israel. The United States, as well as Israel, has always been a target.
In Vienna, where negotiations have been dragging on for days, Iran, the U.S. and five other world powers agreed to extend their current, temporary nuclear deal through Monday, giving themselves more time to try to reach a breakthrough.
Earlier in the day, a crowd of about 50,000 people took part in the rally in sizzling heat at Tehran's Palestine Square, while others celebrated in hundreds of towns and cities across the country.
Saudi Arabia, a regional rival to Iran, came in for harsh treatment, as did the United States and Israel. Yemen, the impoverished Arab country where Iran is supporting Houthi rebels against the Saudi-backed government-in-exile in a multi-sided civil war, was hailed as the "new Palestine" because of what Iranians see as its mistreatment by outsiders.
"The crime of Israel is the crime of America!" a voice blared over a loudspeaker.
"Death to America and death to Israel," the crowd shouted back.
U.S. and Israeli flags were set afire. Posters showing President Obama, Israeli Prime Minister Benjamin Netanyahu and Saudi King Salman were consumed by flames.
The government helped build the crowd by busing in participants. Others took subways that were free of charge for the occasion.
For good measure, the crowds also echoed the complaints of Iran's negotiators in Vienna that U.S. officials have been backtracking on their commitments at the 2-year-old talks.
The negotiations are aimed at working out a deal to end the dispute over Iran's nuclear activities. Officials on both sides have said it could improve a relationship that has been bitter since the revolution.
But participants at the rally for Quds (Jerusalem) Day didn't seem ready to forget the old grievances.
Mehdi Chamran, chairman of the Tehran City Council, was asked how he could be denouncing the United States while Iranian negotiators were trying to cooperate with it in reaching a nuclear deal.
"Iran is negotiating, but it is America and [Secretary of State] John Kerry who is reneging on what has been agreed," Chamran said.
Hossein Shariatmadari, managing editor of the conservative Kayhan newspaper, defended Iranian Foreign Minister Mohammad Javad Zarif, who is often a target of conservatives.
"As far as Mr. Zarif is resisting the excessive demands of America and its allies, he is our respectable chief negotiator," Shariatmadari said. "If the negotiations fail, America should be blamed."
Special correspondent Mostaghim reported from Tehran and Times staff writer Richter from Vienna.