President Donald Trump has been briefed on a wide range of covert and military tools for use in Iran, two Department of Defense officials told the BBC's US partner, CBS News.

Long-range missile strikes remain an option for a potential US intervention, but Pentagon officials have also presented cyber operations and psychological campaign responses, the sources said.

Trump announced a 25% tariff on goods from countries with commercial ties to Iran on Monday, as rights groups say more than 600 protesters have been killed in three weeks of anti-government protests.

Iran's foreign minister has said Tehran is open to talks with Washington, but remains "prepared for war".

Trump's national security team is expected to hold a meeting at the White House on Tuesday to discuss options for Iran, the sources said, but it is unclear whether the president himself will be in attendance.

The US president had earlier said that his military was weighing "very strong options" to intervene if more protesters were killed. Trump said Iranian leaders had called him "to negotiate", but added that the US "may have to act before a meeting".

Frustration over the collapse of the Iranian currency and economic mismanagement has expanded into a crisis of legitimacy for Iran's Supreme Leader Ayatollah Ali Khamenei.

On Monday, White House Press Secretary Karoline Leavitt said an Iranian official had also contacted Trump's special envoy Steve Witkoff, adding that Tehran's public stance is "quite [different] from the messages the administration is receiving privately".

However, she warned that the US president is "unafraid to use military options if and when he deems necessary".

The two sources, who requested anonymity to discuss national security matters with CBS, said that any US military response in Iran will likely involve air power, but that planners are also considering options to disrupt Iranian command structures and communications.

The US has urged its citizens in Iran to leave or have a plan to depart the country that does not require US government assistance.

Khamenei accused the US of "deceit" and relying on "treacherous mercenaries", while praising state-organised pro-government rallies held in Iran on Monday.

He said the "Iranian nation is a powerful one, is aware and knows its enemies and is present in every scene".

State media said large crowds gathered in several cities following calls for pro-government demonstrations. BBC Persian has seen text messages inviting people inside the country to attend these demonstrations, while also warning them not to take part in anti-government protests.

Separately on Monday, Trump said on his Truth Social platform he would impose a 25% tariff on goods from countries that are "doing business" with Tehran, without elaborating.

"This order is final and conclusive," he added.

Iran, already under severe US sanctions, faces a collapsing currency and inflation that has pushed food prices up by as much as 70%. Food makes up about one-third of Iran's imports, and further restrictions, caused by the tariffs, could worsen shortages and costs.

The White House did not share additional information about the tariffs. China is Iran's largest trading partner, followed by Iraq, the United Arab Emirates, Turkey and India.

The move could put more pressure on Tehran as the Iranian government escalates a crackdown on anti-government demonstrations.

Meanwhile, Reza Pahlavi, the son of Iran's last shah who lives in exile in the US, has urged Trump to intervene "sooner" to limit the number of deaths among protesters.

In an interview with CBS News, Pahlavi said the current Iranian government was "trying to trick the world into thinking that (it) is ready to negotiate once again".

He described Trump as "a man that means what he says and says what he means" and who "knows what's at stake".

"I think the president has a decision to make fairly soon," Pahlavi said.

At least 648 protesters in Iran have been killed, including nine people under the age of 18, according to Norway-based human rights group Iran Human Rights (IHRNGO). Sources inside Iran have told the BBC the death toll could be much higher.

The BBC and most other international news organisations are unable to report from inside Iran. An internet blackout since Thursday evening has made it difficult to obtain and verify information. (BBC)

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