"The United States supports the Iranian people in their peaceful protests against the regime that is supposed to lead them", the statement says.
The spokeswoman also said that Washington condemns the stringent restrictions on communications used against demonstrators.
Earlier in the day, Iranian Foreign Ministry spokesman Abbas Mousavi noted that he considers the previous US statement on protests in Iran to be an interference in the country's internal affairs. Prior to this, US State Department spokeswoman Morgan Ortagus said the US condemned the alleged attempts by the Iranian authorities to block the Internet in the country amid protests, and also announced US support for the "long-suffering Iranian people".
Anti-Government Protests in Iran
Iran is now swept by protests against an increase in gasoline prices. One man was reportedly killed during a rally on Friday.
Iranian Supreme Leader Ali Khamenei has stated that the protests in the country were spurred by foreign influence.
"Some people would definitely get upset over this decision... but damaging and setting fire (to property) is not something (normal) people would do. It is hooligans. Sabotage and arson are done by thugs, not our people. The counter-revolution and Iran's enemies have always supported sabotage and breaches of security and continue to do so", the Iranian state TV quoted Ayatollah.
The United States has long been putting pressure on Tehran, with US Secretary of State Mike Pompeo threatening recently to destroy the country's economy if it does not "change its behaviour".