In this May 24, 2021 photo, the flag of Iran is seen in front of the building of the International Atomic Energy Agency (IAEA) Headquarters in Vienna, Austria. (PHOTO / BLOOMBERG)

TEHRAN - Iran denied on Saturday the existence of any "undeclared" nuclear material in the country, as a response to questions raised in a recent report by the International Atomic Energy Agency (IAEA) about its nuclear activities, the official news agency IRNA reported.

In a report by IAEA Director General Rafael Grossi, which was finished on May 31 and disclosed on June 7, Grossi said the IAEA "is still seeking explanations from Tehran for the presence of uranium particles of anthropogenic origin identified by the agency at three undeclared locations in Iran -- Turquzabad (2019), Varamin (2020) and Marivan (2020)."

Iran's permanent mission to the UN offices and other international organizations in Geneva said in a statement that questioning the nature of Iran's "peaceful" nuclear program has no justification while the country's nuclear activities have entirely been under the IAEA's supervision

In his report, Grossi also expressed "deep concern that nuclear material had been present at these undeclared locations."

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Responding to the IAEA report, Iran's permanent mission to the UN offices and other international organizations in Geneva said in a statement that questioning the nature of Iran's "peaceful" nuclear program has no justification while the country's nuclear activities have entirely been under the IAEA's supervision, monitoring and careful verification.

These claims are based on "fabricated" information provided by Israel with "sinister intention," it noted.

In November last year, Iran rejected as "baseless" the claim from an IAEA's resolution, proposed by the United States, Britain, France and Germany, that "traces of uranium" were found at a number of "undeclared" sites.

The IAEA director general paid a two-day visit to Iran's capital Tehran in early March when the two sides agreed to further interactions based on Iran's cooperation and greater openness to the agency's inspections.

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On May 30, IRNA reported that Tehran and the IAEA have closed two cases of outstanding differences regarding Iran's nuclear program after technical negotiations.