The Biden administration expects Iran will be able to amass enough material to produce a nuclear weapon in less than a year — even if the 2015 agreement among Washington, Tehran and five other nations is revived, according to a new report.

White House officials concluded late last year that Iran’s nuclear program was too far advanced to ​roll back the so-called “breakout period” to the 12 months specified in the original deal negotiated by the Obama administration, the Wall Street Journal reported Thursday.