“Iran stole classified documents from the UN's Atomic Agency IAEA and used that information to systematically evade nuclear probes,” Israeli Prime Minister Naftali Bennett wrote on Twitter.
“How do we know? Because we got our hands on Iran's deception plan,” Mr Bennett wrote. His tweet included a link to eight files of documents in English and Farsi, as well as photographs.
Israel believes Iran is seeking to produce atomic weapons, a claim Tehran strongly denies.
The files were part of a cache allegedly taken by Israeli agents from an Iranian nuclear site in 2018.
Neither Tehran nor the International Atomic Energy Agency (IAEA) immediately responded to requests for comment about the allegations, which appeared to be part of an Israeli campaign to dissuade big powers from renewing a 2015 Iranian nuclear deal in now-stalled Vienna negotiations.
Earlier on Tuesday, Tehran condemned as “not fair” an IAEA report on undeclared nuclear material found at three sites in Iran, as talks on reviving a 2015 deal remain deadlocked.
That deal with world powers, formally known as the Joint Comprehensive Plan of Action (JCPOA), gave Iran relief from crippling economic sanctions in exchange for curbs on its nuclear activities.
But former US president Donald Trump unilaterally pulled out in 2018 and reimposed debilitating sanctions, prompting Iran to begin rolling back on its own commitments.
Israel is adamantly opposed to the original agreement and any effort to restore it.
In its report, the IAEA said it still had questions which were “not clarified” regarding nuclear material previously found at three sites — Marivan, Varamin and Turquzabad — which had not been declared by Iran as having hosted nuclear activities.
It said its long-running efforts to get Iranian officials to explain the presence of nuclear material had failed to provide answers.