The head of the Israel Atomic Energy Commission accused Iran on Wednesday of “deception and concealment,” warning the international community that the Islamic Republic was looking to buy time for its nuclear program.

Speaking at the annual meeting of the International Atomic Energy Agency in Vienna, Shaul Chorev said, “The picture that the Iranian representatives are portraying regarding openness and transparency of their nuclear program … stands in sharp contradiction with Iran’s actual actions and the facts on the ground.”

The issue was not whether Iran has “modified its diplomatic vocabulary … but whether it is addressing seriously and in a timely manner outstanding issues that have remained unresolved for too long,” Chorev told representatives.

The IAEA’s latest report on Iran said the country had prepared more than 1,000 advanced uranium enriching machines for start-up and installed a significant number of additional centrifuges.

Chorev castigated Iran for “deception and concealment, creating a false impression about the status of its engagement with the agency … with a view to buy more time in Iran’s daily inching forward in every aspect of its nuclear military program.”

He also blasted Arab states for using the IAEA meeting to “repeatedly bash” Israel and urged members to reject an Arab-sponsored draft resolution calling on Israel to join a global anti-nuclear weapons pact, reported Reuters.

In Tehran, meanwhile, Iran’s nuclear chief denied reports that recently elected President Hasan Rouhani was willing to shut down the underground Fordo nuclear facility in exchange for an easing of sanctions.

“The closure of the Fordo site is a sheer lie,” Ali Akbar Salehi was quoted by the state-run Fars news agency as having told reporters on Wednesday.

Citing intelligence sources, the German magazine Der Spiegel reported this week that Rouhani might consider closing down Fordo, near the holy city of Qom, and allowing international observers to supervise the destruction of its centrifuges, if the West were to lift the sanctions placed on Iran’s oil industry and central bank.

Rouhani could make the offer later this month at the United Nations General Assembly in New York, the report said.