Earlier, Senate Foreign Relations Committee Ranking Member Jim Risch in a tweet suggested the US was considering providing Iran with guarantees that included ending the International Atomic Energy Agency's probe, protecting Western companies, and allowing Iran to accelerate its nuclear program if a future administration exits the deal.
"Nothing here is true," the NSC wrote via Twitter on Thursday in response to Risch's allegations. "We would never accept such terms. We also would not have left a deal that was working only to see Iran massively accelerate its nuclear program."
Later, NSC spokeswoman Adrienne Watson denied similar allegations that were found in a report by the UK-based Iran International news site.
"Reports that we have accepted or are considering new concessions to Iran as part of reentering the 2015 nuclear deal are categorically false," Watson said.
On Wednesday, former national security adviser John Bolton warned that President Joe Biden could make a grave mistake if his administration offers a concession to Iran that guarantees that a future US president would be restricted from pulling out of a renewed JCPOA.
The State Department confirmed on Tuesday that the Biden administration received Iran's comments on the European Union's proposal to revive the agreement and that it is in the process of studying Tehran's response.