Iran has signalled it favours a de-escalation after 10 days of heightened tensions with the US during which both sides fired missiles and Tehran accidentally shot down a passenger aircraft.
Security was stepped up in Iran's capital Sunday (January 12th) after a vigil the previous night for those killed in the air disaster turned into an angry protest.
Videos surfaced Monday that apparently showed anti-government protests were met with tear gas and left at least one person wounded.
US President Donald Trump had warned Iran in a tweet Sunday against killing protestors, saying that the world and, "more importantly, the USA is watching".
US Defense Secretary Mark Esper said Trump was still willing to "sit down and discuss without precondition a new way forward" with Iran.
Tehran said it favoured an easing of tensions after the US killed Islamic Revolutionary Guard Corps Quds Force (IRGC-QF) commander Maj. Gen. Qassem Soleimani in a Baghdad drone strike on January 3rd.
In a meeting between Iran's President Hassan Rouhani and the visiting emir of Qatar, both sides agreed de-escalation is the "only solution" to the regional crisis, the Qatari ruler said.
"We agreed... that the only solution to these crises is de-escalation from everyone and dialogue," Emir Sheikh Tamim bin Hamad Al Thani said on what was believed to be his first official visit to the Islamic republic.
For his part, Rouhani said: "We have decided to have more consultations and co-operation for the security of the entire region."
Iran's president also met with visiting Pakistani Foreign Minister Shah Mehmood Qureshi, whose country has offered to mediate between Tehran and Riyadh.
In a meeting Sunday with Saudi Crown Prince Mohammed bin Salman, Japanese Prime Minister Shinzo Abe warned military conflict with Iran will have an impact on global peace and stability, Japanese foreign ministry spokesman Masato Ohtaka said.
In a briefing to parliament, IRGC commander Hossein Salami, said the missiles it fired last Wednesday on Iraqi bases hosting US troops were not aimed at killing American personnel.
The US said no American personnel were harmed in the attacks.
Tear gas against protestors
Germany's foreign ministry said Monday that the Iranian people must be allowed to "protest peacefully and freely" and express their "grief and also their anger" after the plane disaster.
Demonstrations broke out for a second night in a row after Iran admitted to having shot down a Ukrainian passenger jet by mistake on January 8th, killing all 176 people on board.
Videos circulating on social media appeared to show large crowds chanting slogans against the country's authorities in Tehran's iconic Azadi Square south of the centre.
Multiple videos, including several shared by the New York-based Centre for Human Rights in Iran, appeared to show people screaming and scattering as tear gas was fired into crowds in the major Tehran artery of Azadi Street.
AFP could not independently verify the exact times or locations of the videos, which are often shared via Telegram channels or other messaging services, but could ascertain that they had not appeared online before Sunday.
In a video purporting to be from the city of Amol in the Mazandaran region on the Caspian Sea, a crowd marches, shouting, "We do not want the Islamic republic".
State TV on Saturday reported that "anti-regime" protests were held in the capital in a rare acknowledgement of such demonstrations.
Iran had denied for days Western accusations that the Ukrainian International Airlines Boeing 737 had been shot down by a missile, with the military admitting the catastrophic error on Saturday.
Later that evening, a memorial at Tehran's Amir Kabir University in honour of those killed turned into a demonstration that was attended by hundreds of students.
Protestors shouted "death to liars" and demanded the resignation and prosecution of those responsible for downing the plane and allegedly covering up the accidental action.
On the day after the rally there was a heavy police presence, notably around Azadi Square.
Riot police armed with water cannon and batons were seen at Amir Kabir, Sharif and Tehran universities as well as Enqelab Square.
Around 50 Basij militiamen brandishing paintball guns, potentially to mark protestors to authorities, were also seen near Amir Kabir.
On Monday, Iran denied that there had been any cover-up of the shooting down of the plane.