Hundreds of thousands across Iran marked the anniversary of its 1979 Islamic Revolution on Tuesday amid some of the highest tensions ever between Tehran and the U.S. in the past four decades.

While Iranian President Hassan Rouhani gave a speech in Tehran’s iconic Azadi Square denouncing the U.S., he also focused on encouraging the country to vote in upcoming parliamentary elections, even after officials disqualified thousands from running, including 90 current lawmakers.

Iran views high turnout as a vote of confidence in the country’s Shiite theocracy, something it wants to show as public anger still simmers over the country accidentally shooting down a Ukrainian jetliner in January that killed all 176 people on board. Tehran for days denied its forces shot down the passenger plane before admitting to it in the face of mounting Western pressure.

The shoot down also marred funeral processions that drew millions of mourners for Revolutionary Guard Gen. Qassem Soleimani, killed in a U.S. drone strike in Baghdad.

“We should not withdraw from the ballot boxes,” Rouhani called out to the thousands in the crowd who rallied in the city in freezing winter weather. “The ballot boxes are our savior.”

There’s also anger over Iran’s long-faltering economy, which has been hard hit by the American sanctions. In November, protesters angered by Iran raising government-set gasoline prices by 50% blocked traffic in major cities and occasionally clashed with police. Amnesty International says more than 300 were killed in violent protests and a subsequent government crackdown. Iran’s government did not release any death toll though lawmakers said thousands were detained.

Rouhani called on voters to still turnout despite “possible complaints and criticism.”

“I beg you not to be passive,” he said.

State media said the rallies took place in more than 5,000 cities, towns and districts all around Iran.

This year’s anniversary celebrations come amid ever-increasing bitterness between Tehran and Washington. Tensions have spiked since President Donald Trump withdrew the U.S. from Iran’s nuclear deal with world powers in May 2018. A series of attacks across the Mideast culminated with the U.S. launching the drone strike that killed Soleimani in January. Iran retaliated with a ballistic missile attack targeting U.S. forces in Iraq, injuring over 100 U.S. troops.

Iranian Foreign Minister Javad Zarif in a tweet advised Trump to change his policies on Iran after the turnout for the anniversary showed that Iranians are united.

“Ïranians turned out in huge numbers to rally on the 41st anniversary of their revolution — and to honor their fallen heroes,” he said.

State television referred to this year’s anniversary as “Soleimani Dawn.” His image could be seen on signs carried by demonstrators, as well as a large poster off to Rouhani’s side during his speech.

The Iranian president spent much of his speech praising Soleimani, calling him both a great military commander and a “senior diplomat.” Soleimani headed the paramilitary Guard’s expeditionary Quds Force, which works across the Mideast with allies in Iraq, Lebanon, Yemen and elsewhere. The U.S. has long blamed Soleimani for the spread of powerful roadside bombs in Iraq that killed and wounded American troops after the 2003 invasion of Iraq.

Those taking part in the demonstration in Tehran, in which protesters burned American and Israeli flags, offered harsh criticism of the U.S.

“America can’t do a damn thing through the sanctions,” said Ozra Shahbakhti, 50, repeating an earlier comment made by Supreme Leader Ayatollah Ali Khamenei. “Even if we die from poverty and hunger we will not compromise with America, no way. I’m telling this to officials, foreigners and America.”

Ali Akbar Nikkei, 36, put the blame directly on Trump.

“You stretch your hand for friendship towards us and then you assassinate our great general and consider this a victory?” Nikkei said. “You are too desperate to bring Iran to its knees.”

Iran’s Islamic Revolution began with widespread unrest over the rule of Shah Mohammad Reza Pahlavi. The shah, fatally and secretly ill with cancer, fled Iran in January 1979. Ayatollah Ruhollah Khomeini then returned from exile and the government fell on Feb. 11, 1979, after days of mass demonstrations and confrontations between protesters and security forces.

Iran later would vote to become an Islamic Republic, a Shiite theocracy with Khomeini as its first supreme leader with final say over all matters of state. Anger over America allowing the shah into the country to receive cancer treatment in New York would later spark the takeover of the U.S. Embassy in Tehran by student militants and the subsequent hostage crisis, which kindled decades of enmity.