Israel’s prime minister has accused Iran of having secretly pursued a nuclear programme amid rising tensions in the Middle East.

Unveiling a cache of files purporting to show that Iran “brazenly lied” when it said it did not have a nuclear programme, Benjamin Netanyahu gave a theatrical presentation on Monday claiming to have “conclusive” evidence of the “secret programme”.

His speech came against a backdrop of sustained efforts by the Trump administration and its allies at home and in the Middle East to cancel, or at least renegotiate, the 2015 nuclear pact signed between Iran and the US, France, Russia, Germany, China, the UK and the European Union.

“You may well know that Iran’s leaders repeatedly denied ever pursuing nuclear weapons … well tonight I’m here to tell you one thing – Iran lied, big time,” Netanyahu said.

He claimed that Iran, after signing the nuclear deal, intensified its efforts to hide files pertaining to its nuclear programme.

“A few weeks ago, in a great intelligence achievement, Israel obtained half a tonne of the material inside these vaults,” Netanyahu said before proceeding to show “55,000 pages” and another “55,000 files on 183 CDs”.

No big surprise

Much of what Netanyahu presented is unlikely to surprise world powers, which have long concluded that Iran was pursuing atomic weapons before the nuclear agreement was signed nearly three years ago.

Before Monday’s announcement, Netanyahu cancelled a speech in parliament and convened an emergency meeting of his security cabinet at Israeli military headquarters in Tel Aviv.

Pres. Trump is jumping on a rehash of old allegations already dealt with by the IAEA to “nix” the deal. How convenient. Coordinated timing of alleged intelligence revelations by the boy who cries wolf just days before May 12. But Trump’s impetuousness to celebrate blew the cover. https://t.co/5gxmmZcrF7 — Javad Zarif (@JZarif) April 30, 2018

Netanyahu has been a leading critic of the nuclear agreement, saying it fails to prevent Iran from gaining nuclear weapons capability.

He has also welcomed US President Donald Trump’s pledges to withdraw from the Iran deal if it is not changed.

Trump praised Netanyahu’s presentation as “good”, saying it and other recent events show he has been “100 percent right” about Iran.

Iran responds

Later on Monday Javad Zarif, Iran’s foreign minister, denounced Netanyahu’s address as a stunt.

“The boy who can’t stop crying wolf is at it again,” he said on Twitter, referring to Netanyahu’s 2012 UN General Assembly presentation that used props to allege Iran’s nuclear threat.

Iranian state TV said called Netanyahu’s accusations propaganda.

“His remarks was not new … full of baseless accusations … and propaganda against Iran’s nuclear work,” it said.

{articleGUID}

Marwan Bishara, Al Jazeera’s senior political analyst, said Netanyahu may have ulterior motives for making his address.

“Netanyahu has a very political incentive especially now with Trump trying to decide about the Iran nuclear deal,” he said.

“He has political incentive to manipulate the facts and exaggerate whatever information he has.”

Other analysts agreed.

“Netanyahu’s presentation was more of a political presentation and offered no new intelligence on Iran’s nuclear programme,” Fatemeh Aman, an Iran analyst based in Washington, DC, told Al Jazeera.

“Moreover, it is rather very strange that Netanyahu claims that Israel has real intelligence on Iran’s nuclear programme that somehow was missed by the extensive inspection regimes installed by the IAEA and the US and other Western intelligence organisations.”

Netanyahu’s accusations also appear to contradict a US state department report published earlier this month.

It said at the end of December 2017: “Iran continued to fulfill its nuclear-related commitments under the Joint Comprehensive Plan of Action (JCPOA)… Iran’s commitments to allow increased IAEA verification and monitoring … and to not engage in certain work that could contribute to the development of a nuclear weapon continue indefinitely.”

{articleGUID}

Earlier on Monday, an Iranian news agency said missile attacks overnight in northern Syria killed more than a dozen pro-government fighters, many of them Iranians.

There was no official confirmation of the death toll or what specific targets were, but the air strikes prompted speculation on who carried it out, with most reports suspecting Israel was behind it.

Syrian state TV called it a “new aggression on military positions” in Hama and Aleppo provinces, but was not specific.

Al Jazeera’s Ali Younes contributed to this report