Iran on Sunday threatened to cancel the nuclear deal with world powers unless a probe into allegations of its past weapons research is closed, AFP reported.

The declaration, by a top Iranian security official, comes after the head of the UN nuclear watchdog said a report into the possible military dimensions of Iran’s activities would not be “black and white.”

Iran has always denied seeking to develop an atomic weapons capability, insisting its nuclear program is for peaceful energy production and medical purposes only.

Referring to the Joint Comprehensive Plan of Action, the July 14 agreement’s official name, Admiral Ali Shamkhani on Sunday said anything short of the International Atomic Energy Agency’s (IAEA) probe being closed was unacceptable to Iran.

Shamkhani is secretary of Iran’s Supreme National Security Council, the country’s highest security body, noted AFP.

The committee reports to supreme leader Ayatollah Ali Khamenei, who has the final word on all policy decisions.

Shamkhani said the six countries which struck the deal with Iran (Britain, China, France, Russia, the United States and Germany) must drop the possible military dimensions issue.

The IAEA probe concerns allegations, rejected by Iran, that at least until 2003 it conducted research into how to make a nuclear weapon.

The UN watchdog recently released a report which determined that Iran had violated the terms of its nuclear deal with the West by increasing its stockpile of low-enriched uranium in the past three months by 460.2 kilograms.

However, according to a senior diplomat, the current increase is the result of a normal fluctuation and “there is nothing special in that.”

Earlier this month it was also revealed that Iran had stopped dismantling its centrifuges at the Natanz and Fordow uranium enrichment plants, breaching the nuclear deal that calls for the dismantling.

Despite revelations that his country is breaching the deal, Iranian President Hassan Rouhani recently threatened to abandon the accord all together, if the United States imposes any new sanctions unrelated to Tehran’s nuclear program.