Iran’s supreme leader, Ayatollah Ali Khamenei, has dismissed lingering protests sparked by economic crisis as schemes of vandals who were “ruining their own streets” to “please” American President Donald Trump.

In a televised speech in Tehran on Friday, Mr Khamenei accused protesters of vandalising public properties just to “please” the U.S. president, who had threatened to “hit” Iran “very hard” if government forces kill protesters.

Mr Khamenei said his government “will not back down” in the face of protests that have rocked the country since December 28.

“There are some agitators who want to please the American president by destroying public property,” Mr Khamenei said. “A united Iranian people will defeat all enemies. I urgently call on Trump to focus on the problems of his own country.

Mr Khamenei, 86, who has been Iran’s leader for over three decades, said, “Last night in Tehran and in some other places, a group of vandals came and damaged buildings belonging to their own country just to please the president of the United States.”

Responding to Mr Trump’s threats, Mr Khamenei lashed out at the American president for siding with vandals.

“He (Trump) wants to side with the rioters and harmful individuals,” Mr Khamenei said. “If he can, he should go and run his own country.”

Amid Iran’s towering inflation, standing at 42 per cent and its currency, the rial, plummeting to an all-time low of 1.4 million rials per dollar, protesters, merchants, traders, and university students have hit the streets, disrupting commercial and public activities across the country.

Since the protests broke out, at least 42 people, including minors, have been killed in a clampdown by security agencies. On Thursday, Iran suffered an internet blackout.

Human Rights Activists News Agency on Wednesday reported that “the death toll from the past 12 days of protests has reached 42 people, including five minors under 18 and eight security personnel or officers.” 

To placate the swelling population of protesters, Fatameh Mohajerani, the Iranian government spokeswoman, on Monday announced on state-owned television a $7 stipend for each Iranian amid protests sweeping the country.  

The $7 stipend, Ms Mohajerani said, was aimed at “preserving households’ purchasing power, controlling inflation, and ensuring food security.”

The protests have lingered, spreading to at least 285 locations in 92 cities across, while 27 provinces have witnessed protest gatherings since they began 12 days ago.