BBC: Shops were shut and thousands of people took to the streets of the capital. Riot police later fired tear gas to disperse the demonstrators as they marched towards parliament. It was the biggest protest in Tehran since 2012, when international sanctions related to Iran's nuclear activities were crippling its economy. The BBC's Kasra Naji says those protests led ultimately to a change in government and to Iran agreeing to substantive talks on a nuclear deal with world powers.
A dollar is currently worth as much as 90,000 rials, compared with 65,000 rials just before Mr Trump's announcement and 42,890 at the end of 2017.
I was just going to post that 30,000 is the official exchange rate, but the real or black market rate is double that.