The US dollar, which traded at about 140,000 rials in 2018, has risen roughly eight-fold since Donald Trump restored US sanctions on Iran seven years ago.
The current dollar rate of 1.16 million rials is just shy of the all-time high of 1.17 million recorded on September 30.
The reimposition of UN sanctions in September deepened the currency shock, Parliamentarian Valiollah Bayati said last month. Addressing President Masoud Pezeshkian, Bayati said public anxiety was mounting.
The sanctions were restored 30 days after Britain, France and Germany triggered the so-called snapback mechanism under the UN Security Council Resolution 2231, citing Iran's failure to comply with its nuclear obligations.
The move restored UN penalties previously suspended under the resolution, tightening external constraints on Iran’s economy.
Farid Mousavi, a member of parliament’s economic committee, warned earlier this month that the currency rise could accelerate in coming weeks. “With inflation continuing at this pace, a 1.3 million-rial dollar rate in winter is not far-fetched."