(ap) -- State TV's website on Tuesday quoted Ali Akbar Salehi as saying: "If we make the determination, we are able to resume 20 percent-enrichment in at most five days."
Iran gave up the majority of its stockpile of 20-percent enriched uranium as part of the 2015 nuclear deal with world powers.
The nuclear deal, which lifted sanctions on Iran, currently caps the Islamic Republic's uranium enrichment at under 5 percent.
Iran long has said its nuclear program is for peaceful purpose.