Washington: US President Donald Trump has pledged unspecified support for Iranians trying to “take back” their government, extending a drumbeat of encouragement for countrywide protests.

“Such respect for the people of Iran as they try to take back their corrupt government,” Trump tweeted yesterday.

“You will see great support from the United States at the appropriate time!” he said.

His comments came as US officials said the White House intends to introduce sanctions against elements of the Iranian regime or its supporters involved in a crackdown against countrywide protests.

Media reports have said Iran’s elite Revolutionary Guards have deployed forces to three provinces to put down an eruption of anti-government unrest after six days of protests that have rattled the clerical leadership and killed 21 protesters.

Senior American officials also said the US may seek emergency session at UN Human Rights Council in Geneva on Iran.

The Trump administration has already demanded a snap Security Council meeting to debate the unrest.

Trump on Tuesday described the regime as “brutal and corrupt”.

His top diplomat at the UN, Ambassador Nikki Haley, used her public platform to recite protesters’ slogans and declared that “the people of Iran are crying out for freedom.”

Much of Trump’s response has focused on playing up perceived errors by the Obama administration, not least a deal that gave Iran sanctions relief in exchange for curbs on its nuclear programme.

“We are looking across the board,” the US official said of the planned sanctions, pointing to authorities that allow President Donald Trump to target organisations or individuals involved in human rights violations, censorship or preventing free assembly.

“That requires information, but there is a lot of information out there, so we intend to start assembling that and see what we can do.”

The official said the US would “use all the information sources at our disposal to be able to get actionable information about who is doing the crackdown, who is violating human rights, who is using violence against protesters and to feed that in to our sanctions designation machinery.”

Protests began in Iran’s second largest city Mashhad and quickly spread to become the biggest challenge to the Islamic regime since mass demonstrations in 2009.