US slapped sanctions on five Iranian companies on Thursday and called for an emergency UN Security Council meeting, further stepping up pressure on Tehran over the protests in the country.

The US imposed sanctions against the firms alleged to have been working on an illegal ballistic missile programme, linking the move to the protests.

"These sanctions target key entities involved in Iran's ballistic missile programme, which the Iranian regime prioritises over the economic well-being of the Iranian people," US Treasury Secretary Steven Mnuchin said.

No fresh protests

The US move came even as Iranian authorities declared an end to the turmoil, and pro-government demonstrators rallied across the nation while officials switched focus to addressing the economic concerns that have fueled protests.

On the streets of Tehran, meanwhile, a heavy police presence lingered though there were no reports of fresh protests overnight.

Limited social media activity suggested unrest in provincial towns was also down.

UNSC meet on Friday

Meanwhile, the UN Security Council will hold an emergency meeting on Friday to discuss the wave of protests in Iran, at the request of the United States, the council presidency said.

Russia has criticised the US push for Iran to be discussed at the Security Council and it remained unclear whether Moscow or other council members would try to block the meeting.

The meeting is scheduled for 3:00 pm (2000 GMT), said the mission of Kazakhstan, which holds the council presidency.

"We see no role for the United Nations Security Council in this issue," RIA news agency cited Russian Deputy Foreign Minister Sergei Ryabkov as saying on Thursday.

"Iran's domestic affairs have nothing to do with the United Nations Security Council's role."