Iran's foreign minister on Monday warned neighbouring countries over fomenting insecurity in Iran in a reference to anti-government protests that have roiled the country over the past two weeks.

The remarks by Mohammad Javad Zarif at a security conference in Tehran echoed the Iranian authorities' stance, which alleges that foreign powers including regional rival Saudi Arabia stirred up unrest linked to the protests.

“Some countries tried to misuse the recent incidents,” Zarif said without blaming any specific country, and added that “no country can create a secure environment for itself at the expense of creating insecurity among its neighbours.”

“Such efforts” will only backfire, the official IRNA news agency quoted Zarif as saying.

The anti-government demonstrations first broke out in Mashhad, Iran's second-largest city, on Dec 28 and later spread to several other cities and towns.

The protests were the largest seen in Iran since the disputed 2009 presidential election. T

hey were sparked by a hike in food prices amid soaring unemployment but some demonstrators later called for the government's overthrow and chanted against the country's supreme leader, Ayatollah Ali Khamenei.

At least 21 people were killed and hundreds arrested.

Large pro-government rallies were held in response, and officials have blamed the anti-government unrest on foreign meddling.

In the past few days, Iranian authorities said the protests are waning and on Sunday, Iran's Revolutionary Guard claimed the nation and its security forces had ended the wave of unrest.

The powerful Guard blamed the unrest on the United States, Israel and Saudi Arabia, as well as an exiled opposition group known as the Mujahedeen-e-Khalq, and supporters of the monarchy that was overthrown in the 1979 Islamic Revolution.

Zarif also mentioned an emergency session of the UN Security Council on Friday.

The United States had called the meeting, portraying Iranian protests as a human rights issue that could spill over into an international problem.

US Ambassador to the UN Nikki Haley said the session had put Iran on notice that “the world will be watching” its actions but envoys from several other countries expressed reservations whether the Council was the right forum for the issue.

Zarif on Monday depicted the session as a fiasco and evidence that the Trump administration is “isolated at the international level.”

The world “witnessed that (all other) members of the UN Security Council spoke about preventing the meddling in Iran's internal affairs,” he said.

Zarif also warned that the Islamic State group is still active and a threat in the region and beyond, despite the destruction of its self-proclaimed “caliphate” in Syria and Iraq and called for a “complete crush” of the militant group.

Also Monday, Iran's moderate President Hassan Rouhani said despite the abuse of the protests by outsiders, the authorities should heed the message of the people.

“People rightfully say: 'See us, listen to our words,'” Rouhani said.

He stressed that his policy of economic reform is the “right” way forward and urged for the lifting of bans on messaging apps, including the popular Telegram messaging service, that were shut down during the protests.