WASHINGTON/TEHERAN/MOSCOW/CAIRO - US President Donald Trump said Monday that any country doing business with Iran will pay a tariff rate of 25 percent on any business conducted with the United States.

The order is "effective immediately," Trump announced on Truth Social, adding that it is "final and conclusive."

The statement marks the latest escalation in Washington's economic pressure campaign against Iran, as Trump repeatedly threatened that his administration is weighing "some very strong options" including potential military action.

White House press secretary Karoline Leavitt said earlier Monday diplomacy remains the preferred approach for the United States to deal with Iran, though the Trump administration will not rule out military options if necessary.

"President Trump has always expressed that diplomacy is the first option," Leavitt said on Fox News. "However, he is unafraid to use the lethal force and might of the United States military if and when he deems that necessary." 

Situation in Iran 'under total control'

Tens of thousands of pro-government Iranians flooded the streets on Monday, answering an official call to show solidarity with the state. As state media broadcast images of sprawling crowds at Tehran's Enghelab Square, Foreign Minister Seyed Abbas Araghchi declared that the internal situation is now "under total control."

The pro-government demonstrations, which also took place in cities such as Kerman, Zahedan, and Birjand, were characterized by state broadcasters as a "popular uprising against American-Zionist terrorism." In Shahrud, the rallies coincided with a funeral for security personnel killed during recent unrest. Supreme Leader Ali Khamenei described the gatherings as a stern warning to US politicians to "halt their deceitful actions and stop relying on their traitorous hirelings."

The current wave of instability was triggered last month by a sharp depreciation of the Iranian rial and sweeping reforms to government subsidies. What began as an economic protest quickly morphed into nationwide unrest, leading to violent clashes between police and demonstrators.

Earlier Monday, Araghchi reiterated that the situation in Iran is "under total control" and accused the United States of interference. In a meeting with foreign diplomats, he claimed that nationwide protests had been "turned violent and bloody" to give Trump an excuse to intervene.

Araghchi said Iran is "ready for war but also for dialogue," accusing foreign elements of fueling the demonstrations and vowing that security forces would "hunt down" those responsible. He further claimed that Iran had obtained evidence of US and Israeli involvement in domestic "terrorist activities," including footage showing weapons being distributed to protesters, and said authorities would soon release detainees' confessions. He also added that internet service, blacked out since Thursday, would be restored soon.

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US urges citizens to leave Iran 

The Trump administration on Monday updated a travel warning urging US citizens to leave Iran immediately amid the unrest across the Middle East country.

"US citizens should expect continued internet outages, plan alternative means of communication, and, if safe to do so, consider departing Iran by land to Armenia or Türkiye," said US virtual embassy Iran in a statement, adding that US-Iranian dual nationals must exit Iran on Iranian passports since the Iranian government does not recognize dual nationality.

"US nationals are at significant risk of questioning, arrest, and detention in Iran," it said.

According to the statement, airlines continue to limit or cancel flights to and from Iran, with several suspending service until Friday.

Travel warning

The US Department of State on Monday updated a travel warning urging US citizens to leave Iran immediately amid the unrest across the Middle East country.

Russian condemns US interference 

Sergei Shoigu, secretary of the Russian Federation Security Council, on Monday condemned another attempt by external forces to interfere in Iran's internal affairs, local media quoted the council's press service as saying.

He made the remarks during a telephone conversation with Iran's Supreme National Security Council Secretary Ali Larijani, in which Shoigu expressed condolences over the heavy casualties in Iran, the press service said.

The two sides agreed to maintain close contact and coordinate their positions to ensure security, it said.

Shoigu also reaffirmed Moscow's readiness to further develop bilateral cooperation based on the Comprehensive Strategic Partnership Agreement signed by Russia and Iran in 2025.

Internet in Iran 

Access to the internet in Iran will remain restricted until officials determine that full security has been restored following riots and terrorist acts targeting public institutions, Iran's top cyberspace authority was cited Monday as saying by media reports.