Iran Guards chief says 'finger on trigger', warns US against 'miscalculations'

US President Donald Trump has repeatedly left open the option of new military action against the Islamic republic after Washington backed and joined Israel's 12-day war in June.

A fortnight of protests starting in late December shook the clerical leadership under supreme leader Ayatollah Ali Khamenei, but the movement has petered out in the face of a crackdown that activists say has left thousands dead.

Guards commander General Mohammad Pakpour warned Israel and the United States "to avoid any miscalculations, by learning from historical experiences and what they learned in the 12-day imposed war, so that they do not face a more painful and regrettable fate".

"The Islamic Revolutionary Guard Corps and dear Iran have their finger on the trigger, more prepared than ever, ready to carry out the orders and measures of the supreme commander-in-chief -- a leader dearer than their own lives," he said, referring to Khamenei.

His comments came in a written statement quoted by state television marking the national day in Iran to celebrate the Guards, a force whose mission is to protect the 1979 Islamic revolution from internal and external threats.

Activists accuse the Guards of playing a frontline role in the deadly crackdown on protests. The group is sanctioned as a terrorist entity by countries including Australia, Canada and the United States and campaigners have long urged similar moves from the EU and UK.

Pakpour took over as Guards commander last year after his predecessor Hossein Salami was one of several key military figures killed in an Israeli strike during the 12-day war, losses which revealed Israel's deep intelligence penetration of the Islamic republic.

Giving their first official toll from the protests, Iranian authorities on Wednesday said 3,117 people were killed.

The statement from the Islamic republic's foundation for martyrs and veterans sought to draw a distinction between "martyrs", who it said were members of security forces and innocent bystanders, and what it described as "rioters" backed by the US.

Of its toll of 3,117, it said 2,427 people were martyrs.

However, rights groups say the heavy toll was caused by security forces firing directly on protesters and that the actual number of those killed could be far higher and even extend to over 20,000.

Speaking at the World Economic Forum in Davos, Israeli President Isaac Herzog said "the future for the Iranian people can only be in a regime change", adding that "the Ayatollah regime is in quite a fragile situation".