(Adds comments, details, background)
By Phil Stewart
WASHINGTON, Jan 3 (Reuters) - The United States aims to collect "actionable information" that could allow it to pursue sanctions against Iranian individuals and organizations involved in a crackdown on protesters, a senior U.S. official said on Wednesday.
The move is part of an effort by President Donald Trump's administration to swiftly side with anti-government protesters who have rattled Iran's clerical leadership, including at the United Nations and through Trump's own proclamations of support.
Iran's elite Revolutionary Guards have deployed forces to three provinces to put down the protests, which began last week out of frustration over economic hardships suffered by youths and the working class.
The senior Trump administration official, who spoke on condition of anonymity to explain U.S. thinking about the protests, acknowledged that the demonstrations were unexpected and that Washington was actively collecting information about the Iranian crackdown.
The idea was to obtain information and "to feed that into our sanctions designation machinery," noting that the Trump administration already had robust authority to target individuals or organizations for human rights abuses, censorship or for preventing the free assembly of protesters.
"Human rights, censorship, free assembly - we have existing authorities that we can bring into action. That requires information," the official said.
"But there's a lot of information out there so we intend to start assembling that and see what we can do."
CALLING FOR REPUBLIC'S DOWNFALL
Anti-government rallies, held in defiance of the pervasive security services, have called for the downfall of the Islamic Republic, posing one of the most sustained challenges to the established order of the major oil-exporting state since the 1979 Islamic Revolution that overthrew the U.S.-backed Shah.
The protests have heaped pressure on President Hassan Rouhani, a relative moderate who championed a deal struck with world powers in 2015 to curb Iran's disputed nuclear program in return for the lifting of most international sanctions.
The U.S. official left open the possibility that protests may initially been tied to Rouhani's more conservative opponents, but said it quickly morphed into a spontaneous, broader uprising that caught Tehran off-guard.
Many of the protesters are fuming over what they see as the failure so far of Rouhani's government to deliver on promises of more jobs and investment as a dividend of the nuclear accord.
The U.S. official said the United States believed that Iranians were upset that a disproportional amount of the sanctions relief was directed toward state security services.
Still, it was unclear how the protests might affect Trump's thinking about the 2015 nuclear pact that eased economic pressure on Tehran in exchange for limits on its nuclear program.
Trump must decide by mid-January whether to continue waiving U.S. sanctions on Iran's oil exports under the terms of the international deal.
If he reimposes sanctions on oil, it could increase the economic pain for Iran's leaders. But analysts said it could also send the wrong message about U.S. support for Iran's people in the middle of the boldest challenge to the leadership in a decade.
Asked about those sanctions, the U.S. official said no decision had been reached.
"We have some time," the official said. "We're preparing options for the president. It's just too soon to say." (Reporting by Phil Stewart; Editing by James Dalgleish)
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