'What else is Iran hiding,' asks US after Israel's hidden nuclear-site claims

Tension soared when Prime Minister Benjamin Netanyahu accused Iran of having an undisclosed nuclear weapons site

Iranian Foreign Minister Javad Zarif, centre, arrives for a meeting with IAEA acting director general Cornel Feruta (not pictured) in Tehran, Iran. EPA

The United States on Tuesday said it was 'totally unacceptable' that Iran was not fully cooperating with the International Atomic Energy Agency's investigation of its nuclear programme, but repeated it remained open to talks with Tehran on a "comprehensive deal".

"Any indication that Iran is providing insufficient cooperation to the IAEA on a matter involving potential undeclared nuclear material or activities raises serious and profound questions," the US statement to a quarterly IAEA Board of Governors meeting said.

"Iran's failure to resolve the Agency's concerns on this matter is completely unacceptable and should be of deep concern to all who support the IAEA and its safeguards verification regime."

The US demanded Iran fully cooperate with the UN nuclear watchdog after Israeli claims of previously undisclosed nuclear development sites.

"We should all be asking ourselves, what else is the Iranian regime continuing to hide?" the US told the IAEA board on Tuesday. “Iran must immediately provide the IAEA nothing short of full cooperation,” they added.

The US also told the IAEA board that unlike steps Iran has recently taken to exceed the terms of the 2015 nuclear deal since Washington pulled out of the agreement last year, any move to develop new technologies were not reversible.

“Any gain in understanding from expanded [research and development] work is not reversible, as that knowledge, once gained, will remain with Iran,” the US said.

However, Washington is “open to negotiation with Iran without preconditions,” they said, but added that it would come “when the time is right.”

Iran's Foreign Minister Javad Zarif accused Israel of "crying wolf" and seeking war after Prime Minister Benjamin Netanyahu’s claimed the country has an undisclosed nuclear weapons site.

On Monday, tension between the two countries escalated when Mr Netanyahu gave a presentation that claimed Israel had discovered a nuclear weapons facility in the central Iranian town of Abadeh.

He said that they had found it through information gathered in a trove of documents Israeli agents stole from an Iranian warehouse and made public early last year.

“Iran conducted experiments to develop nuclear weapons,” Mr Netanyahu told reporters, but provided no details or evidence of the experiments.

He did show two satellite pictures, one taken in June that showed the facility intact and a second taken in July that showed parts of the building had been destroyed. He said that it had been destroyed in a cover-up after the facility was discovered by Israel.

"The possessor of the real nukes cries wolf on an alleged 'demolished' site in Iran," Mr Zarif wrote on Twitter. He said Israel wanted a war.

Mr Zarif then shared a 1987 front-page article from The Sunday Times as alleged evidence that Israel is the only nuclear-armed country in the Middle East.

Mr Netanyahu also shared pictures of the presentation and details of Israel's  accusations on Twitter.

“This is what I have to say to the tyrants of Tehran,” one tweet said. “Israel knows what you’re doing, Israel knows when you’re doing it, and Israel knows where you’re doing it.”

GPS co-ordinates provided by Mr Netanyahu did correspond to a set of buildings located in the hills north of Abadeh, according to commercially available satellite images. However, their purpose could not be immediately determined.

The announcement came as the United Nations nuclear watchdog held a meeting in Vienna, where Mr Netanyahu is  hoping the agency will take tougher action against Iran. It also came in the final stages of Israeli national elections, drawing criticism from opponents that the sudden press conference was a campaign stunt.

The International Atomic Energy Agency, the UN nuclear watchdog, has said for years that Iran halted organised efforts to explore possible nuclear weapons in 2003. United States intelligence officials reached the same conclusion.

Israel considers Iran to be its greatest enemy, and Mr Netanyahu has been a leading opponent to the 2015 international nuclear deal with Iran.

He says that Iran is trying to build a nuclear bomb, a charge it denies, and has accused the Iranians of breaching provisions of the agreement.

Last year, President Donald Trump withdrew the US from the nuclear agreement and reimposed sanctions on Iran.

The deal has steadily unravelled since then, and caused tension to soar across the Arabian Gulf and broader Middle East.

The tension has spilt over into fighting between Israel and Iran and its Shiite allies in Lebanon and Syria. Earlier on Monday, Israel said that Iranian-backed Shiite militants in Syria failed in an attempt to fire rockets into Israel, while the Lebanese militant group Hezbollah said it shot down an Israeli drone in Lebanese airspace.