Iran on Friday wrapped up two days of naval exercises in the Persian Gulf -- a show of force aimed at the U.S. just as the Trump administration is reimposing sanctions.

At the same time, protests are popping up in cities all over Iran, only this time, the anger is not directed at America. The protests are largely fueled by frustration with a failing economy.

The size of the crowds in social media videos has been hard to confirm, but their chants are clear.

In one clip, demonstrators in the city of Isfahan shout "death to the dictator," daring to openly defy Supreme Leader Ayatollah Ali Khamenei. They appear to set fire to police cars and throw rocks.

The rallies follow larger ones that started in December and flared up again in June, when protesters demonstrated outside parliament and shut down Tehran's Grand Bazaar.

Iranians are grappling with rising inflation. The country's currency has collapsed, losing nearly half its value since April. And uncertainty is growing as U.S. sanctions are set to start again on Monday, three months after President Trump withdrew from a nuclear deal with Tehran.

"They are having a lot of difficulty right now," Mr. Trump said.

"I hope it works out well," he said, adding, "I have a feeling they'll be talking to us pretty soon."

As economic pressure intensifies, many wealthy Iranians are leaving the country.

One woman said she doubts she'll find work, even with a law degree.

Some Iranians say the economy is so vulnerable to sanctions because it's corrupt and poorly managed. In a highly unusual move, Iranian lawmakers have summoned moderate President Hassan Rouhani to account for the crisis.