Iran’s supreme leader on Friday lashed out at anti-government protesters, saying they were “vandals” acting on behalf of U.S. President Donald Trump by destroying public properties.

In a broadcast on national television, reported by Reuters, Ali Khamenei warned Tehran would not tolerate “mercenaries for foreigners.”

“The Islamic Republic came to power through the blood of hundreds of thousands of honourable people. It will not back down in the face of vandals,” Khamenei said.

His comments came as the country of 92 million found itself largely cut off from the world on Friday, with authorities seeking to quell the sprawling protests by blacking out the internet.

The demonstrations, which began in Tehran’s bazaar on Dec. 28, have been fueled by growing frustrations over a long-running economic crisis, particularly the government’s handling of a sharp fall in the nation’s currency and soaring prices.

The scale of the unrest makes it one of the widespread demonstrations in recent years, according to Human Rights Activists News Agency (HRANA), with dozens reported killed and nearly 2,300 arrested or detained. HRANA, a U.S.-registered non-profit, relies on an activist network inside Iran for its reporting.

The protests have also revived concerns about possible American intervention. Trump said last week that if Iran “violently kills peaceful protesters,” then the U.S. will “come to their rescue.”

“We are locked and loaded and ready to go,” Trump wrote in a post on Truth Social on Jan 2.

Iran’s supreme leader adviser Ali Larijani reportedly responded at the time by saying that U.S. interference in Iran’s protests was equivalent to chaos across the entire region.

Iran, which is a member of OPEC, is a major player in the global oil market.

Oil prices were last seen trading higher as energy market participants continued to monitor concerns over the disruption in Iran.

International benchmark Brent crude futures with March expiry traded up 0.9% at $62.52 a barrel on Friday, while U.S. West Texas Intermediate futures with February expiry stood at $58.29, up 0.9% for the session.

— CNBC’s April Roach and Anniek Bao contributed to this report.