Iran's Rouhani expects US to resume commitments under nuclear deal
Tensions between Tehran and Washington soared during Trump's presidency, especially after 2018 when he withdrew Washington from the landmark nuclear deal and reimposed punishing unilateral sanctions on Iran.
Biden, who defeated Trump at the ballot box in November, has signalled a willingness to return to diplomacy with Iran.
"The sanctions will be broken," he added.
His comments come a day after Iran's supreme leader Ayatollah Ali Khamenei said that Iran should bolster itself to "nullify" the effects of the sanctions imposed by the Trump administration, but should "not delay" in case they can be lifted.
Rouhani echoed Khamenei, saying time should not be wasted.
"We must act in order to nullify the effects of the sanctions... as the supreme leader has said."
"We should not wait, not even one hour, for the lifting of the sanctions. The government must do everything in its power to break the sanctions," Rouhani added.
He said Iran will do "everything possible to achieve" what he described as a "very important instruction" made by Khamenei.