Iran in 'economic war' with US: Rouhani
The comments come a day after mass protests swept through the country over a plunging rial, with some protesters calling on the Iranian leader to resign.
The Iranian parliament was also shut down on Monday as a result of protests outside the building. The event signalled widespread unease in the wake of US President Donald Trump's decision to pull Washington out of the 2015 nuclear deal and restore sanctions on Iran.
"The US cannot defeat our nation, our enemies are not able to get us to their knees," Rouhani said.
He also promised Iranians that the country would be able to withstand US sanctions.
The restoration of US sanctions may cut Iran's hard currency earnings from oil exports, which could trigger a mass sale of rials into US dollars.
In March, the IMF estimated Iran held $112 billion in foreign assets and reserves. Many observers say this will allow the country to withstand sanctions without an external payments crisis.
Iran is also implementing a series of policies in preparation for US sanctions and to control rising prices. These include banning imports for more than 1,300 products.
This week's protests were the first such confrontation between demonstrators and police since similar unrest rocked the country late last year.
In December, demonstrations took place in more than 80 Iranian cities and towns, the largest protests in nearly a decade, over economic conditions. At least 25 people died and nearly 5,000 people were arrested by authorities.
December's protests also took on a rare political dimension, with a growing number of people calling on Supreme Leader Ayatollah Ali Khamenei to resign.
The rial stood at around 40,000 to the dollar in October, when Trump said he would no longer certify Iran's compliance with the nuclear deal. The rial has been falling steadily since then.
The Iranian rial now stands at 90,000 to the dollar on the black market.
Agencies contributed to this report.
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