Reuters has quoted unnamed senior sources near the Iranian supreme leader's "inner circle" as saying 80-year-old Ayatollah Ali Khamenei ordered a nearly boundless crackdown as anti-government protests gained momentum last month, warning assembled officials they would be held responsible if the street unrest did not stop.

In its extensive December 23 report, the agency says Khamenei, who has the final say on political and religious affairs in Iran, "raised his voice and expressed criticism of the handling of the unrest" to President Hassan Rohani, cabinet members, and other senior officials assembled at the supreme leader's fortified official residence on November 17.

"The Islamic republic is in danger. Do whatever it takes to end it. You have my order," Reuters cited one source "close to" Khamenei's "inner circle" as quoting the supreme leader as having said at the meeting.

That was two days after protests began to sweep the country over gas rationing and quickly swelled to include calls for the country's clerical leadership to go.

The crackdown is thought to have been the most violent response to protests in the 40-year history of the theocratic regime that arose after Iran's 1979 Islamic Revolution.

Reuters quoted "three Iranian Interior Ministry officials" as confirming a death toll of about 1,500 during less than two weeks of the November unrest.

Iranian officials have not provided precise numbers of the dead, but say Amnesty International estimates of at least 304 and U.S. State Department suggestions of possibly upward of 1,000 killed are overstated.

They have acknowledged, however, that "some rioters were killed in clashes."

Internet access was shut down all over the country for days at the height of the unrest, but images were smuggled out of fatalities and scenes of violence.

The head of Iran's Supreme National Security Council, Alireza Zarifian Yeganeh, on December 23 dismissed the Reuters report as "false propaganda" and "based on a set of premeditated psychological warfare and lack credibility," according to Iran's Press TV.

Yeganeh said the agency's claims were "totally worthless, not only in terms of security issues and intelligence, but in the field of news and media."

Iranian officials have blamed "thugs" connected to enemies abroad and the United States, Israel, and Saudi Arabia of involvement in the protests, which reportedly occurred in more than 100 cities.

Press TV and other Iranian media have said authorities arrested more than 100 "ringleaders and masterminds" of the violent unrest.

Street protests in late 2017 and early 2018 erupted amid anger over prices and other perceived economic woes and met with a clampdown that included at least 20 deaths and thousands of arrests. That was seen as the biggest wave of unrest since a disputed presidential election brought millions of Iranians into the streets in 2009.

Reuters' sources to the November 17 meeting reportedly "agreed the protesters aimed to bring down the regime."

"The enemies wanted to topple the Islamic republic and immediate reaction was needed," it quoted one of the Iranian sources as saying.

Three of Reuters' sources said Khamenei was "especially concerned with anger in small working-class towns," where support has generally been less critical of the country's leadership.

Reuters said Iran's powerful Islamic Revolutionary Guards Corps (IRGC) declined to comment for its article.

But the agency quoted "a senior member" of the IRGC in the western Kermanshah Province as saying that a late-night meeting on November 18 included instructions from the provincial governor "to end the protests."

"No more mercy," the source recalled being told. "They are aiming to topple the Islamic republic. But we will eradicate them."

Iran's economy and its currency have tumbled since U.S. President Donald Trump withdrew from a 2015 nuclear agreement trading curbs on Tehran's nuclear activities for relief from international sanctions.

Trump's administration has pursued what some U.S. officials have described as a "maximum pressure" policy to force a change of behavior from Iranian officials or to get them back to the negotiating table.

With reporting by Reuters and Press TV