Other pro-government demonstrations were held in Shahin Dezh, in West Azarbaijan province bordering Turkey; the city of Semnan, in the northern Semnan Province; and Shadegan, in the southern Khouzestan Province near Iraq. A similar rally followed Friday prayers in Tehran.
"Why is the United States, a permanent member of the Security Council and one of the authors of the UN Charter, undermining the authority of the Security Council as the main body responsible for maintaining global peace and security?"
More than a week of unrest has seen 22 people die and more than 1,000 arrested, according to Iranian officials, in the biggest anti-government protests for almost a decade.
But Russia's ambassador, Vassily Nebenzia, said the United States was "abusing the platform of the Security Council".
Iran's state TV on Saturday showed government supporters rallying a day after the foreign minister said a USA move to call an emergency U.N. Security Council meeting to discuss anti-government protests was another Trump administration "blunder".
US President Donald Trump on Saturday weighed in on protests in Iran for a second straight day, warning that the country's people want change and "oppressive regimes can not endure forever". We will not be quiet.
Briefing the Security Council, Taye-Brook Zerihoun, Assistant UN Secretary-General for Political Affairs, said the demonstrations taking place in Iran were a fundamental expression of human rights, and a powerful exhibition of fearless people who were so fed up with their oppressive regime that they were willing to risk their lives in protest. "The United States is abusing the platform of the security council", said Russian Ambassador Vassily Nebenzia, whose country has close ties to Iran.
"It's another attempt [at bullying] by the US, which has lost authority and credibility in the eyes of the whole world", said Khoshroo. "Let Iran deal with its own problems".
Khoshoroo alleged that the United States has a long history of intervening in the internal affairs of Iran, including a continuous pattern of disruption in the democratisation process in Iran.
Observing that the Council's primary responsibility is maintaining worldwide peace and security, Wu Haito of China said that it should not be the venue for discussing the human rights situation of any country.
"However worrying the recent events were, they did not constitute a threat to global peace and security".
"One U.S. resident took to social media to order the killing of our security forces ... as well as their families, in their homes".
China also described the meeting as meddling in Iran's affairs.
Iranian Foreign Minister Javad Zarif wrote on his Twitter account that the meeting was "another foreign policy blunder for the Trump administration".
Up to 42,000 people have taken part in the protests. "Another FP [foreign policy] blunder for the Trump administration". The days of pro-government rallies drew crowds in the tens of thousands.