Iran's Revolutionary Guards declare victory over 'foreign-instigated' anti-government protests

"Iran's revolutionary people along with tens of thousands of Basij forces, police and the intelligence ministry have broken down the chain (of unrest)," the Guards said in a statement on their Sepahnews website.

The Guards said the unrest had been "created ... by the United States, Britain, the Zionist regime (Israel), Saudi Arabia, the hypocrites (Mujahideen) and monarchists".

Residents contacted by Reuters in various cities have said the protests had subsided after the government intensified a crackdown by dispatching Revolutionary Guards forces to several provinces.

As protests have ebbed, the government has lifted restrictions it imposed on Instagram, one of the social media tools used to mobilise protesters, according to Reuters.

But access to a more widely used messaging app, Telegram, was still blocked.

Protests in Iran began on Thursday in the north-eastern city of Mashhad, with anti-government rallies quickly spreading to other cities including Tehran, Khorramabad, Karaj and Sabzevar.

The protests spread to more than 80 cities and rural towns and thousands are thought to have taken part in them, making them the biggest show of public defiance since 2009, when Iranians - as part of the newly-formed Green Movement - took to the streets to denounce an election win for former President Mahmoud Ahmedinejad, which they alleged was rigged.

The Revolutionary Guards and their affiliated Basij militia suppressed those protests in 2009, in which dozens of pro-reform Iranians were killed.

The protests this time initially centred around rising living costs, but quickly became focused against the regime in general with chants of "death to the dictator".

In an attempt to shut down protests and manage the unrest, Iran's government had blocked access to the encrypted Telegram messaging app and the photo-sharing app Instagram, which now join Facebook and Twitter in being banned.

At least 21 people have so far died since protests began and over a 1,000 have been arrested.