The United States denied on Monday night a reported secret appendage to the nuclear deal between Iran and world powers that would allow Tehran to yield an atomic bomb by the year 2027."There is no secret document or secret deal," US State Department Deputy Spokesman Mark Toner said. The US response came in light of an AP report Monday that the news agency had allegedly obtained a so-far publicly undisclosed document that lowers the time the Islamic Republic would need to develop a nuclear bomb to six months after the restrictions of the agreement are lifted. The Joint Comprehensive Plan of Action or JCPOA accord significantly reduces Iran's nuclear program for the first 10 years that it is in effect. According to the deal's agreed upon terms, Iran's nuclear breakout period during the first decade of the deal is said to be at least a year.The US State Department official noted that the US has "always been clear" that Iran's nuclear breakout period would be shorter after the first decade of the deal's adherence. Yet, he underlined that "the breakout time does not go off a cliff nor do we believe that it would be cut in half, to six months, by year 11." The AP report came nearly a year after the adoption of the 2015 Joint Comprehensive Plan of Action or JCPOA accord, which Prime Minister Benjamin Netanyahu and various Israeli officials staunchly oppose. The deal was officially implemented, however, in January 2016 after Iran completed a series of requisite tasks.The document was reportedly given to the AP by an unnamed diplomat whose work has focused on Iran’s nuclear program for more than a decade. The report said its authenticity was confirmed by another diplomat.The diplomat who shared the document said it was an add-on agreement to the main deal that is formally separate but actually is an integral part of the deal. Iran and the six countries that negotiated the deal, including the United States, approved the add-on.However, the State Department's Toner said the supposed "secret document" referred to in the report "appears to be Iran's long term enrichment R&D plan that was submitted by Iran to the IAEA as part of its initial Addition Protocol declaration."He added that the JCPOA "explicitly refers to this document," which he said details Iran's plan for centrifuge research under the nuclear deal.While Toner stated that the plan constituted an IAEA "safeguards confidential" document that had not been made public, its substance was made available to the US Congress "on multiple occasions" both before and after the nuclear deal was submitted. "The P5+1 reviewed this plan and we are confident that Iran's enrichment capacity in the years after the initial decade of the JCPOA will undergo measured, incremental growth consistent with a peaceful nuclear program," he said in a statement Monday. JTA contributed to this report.