Israeli Prime Minister Benjamin Netanyahu says Iran has lied about not pursuing nuclear weapons, and has continued to preserve and expand its nuclear weapons knowledge.

Mr Netanyahu revealed on Tuesday (AEST) “secret nuclear files” he says proves Iran covertly pursued nuclear weapons, despite signing a 2015 agreement with global powers to curb its nuclear programme.

“Iran’s leaders repeatedly deny ever pursuing nuclear weapons,” he said  Monday local time from Israel’s defence ministry in Tel Aviv.

“Tonight I’m here to tell you one thing: Iran lied.

“After signing the nuclear deal in 2015, Iran intensified its efforts to hide its secret files. In 2017 Iran moved its nuclear weapons files to a highly secret location in Tehran.”

Mr Netanyahu revealed what he said were “exact copies” of documents obtained by Israeli intelligence, showing 55,000 pages of evidence and a further 55,000 files on a nuclear weapons programme called “Project Amad”.

He said the project had a specific goal of producing five warheads, each with the capacity to carry 10 kilo-tonnes of TNT.

During his presentation, Mr Netanyahu showed Iran had pursued the key elements for a nuclear weapons programme, including designing weapons and preparing for tests.

Iran’s Foreign Minister Mohammad Javad Zarif responded to the Israeli prime minister’s claim in tweet on Monday, saying “BREAKING: The boy who can’t stop crying wolf is at it again. Undeterred by cartoon fiasco at UNGA.”

“You can only fool some of the people so many times,” he wrote.

BREAKING: The boy who can't stop crying wolf is at it again. Undeterred by cartoon fiasco at UNGA. You can only fool some of the people so many times. pic.twitter.com/W7saODfZDK

— Javad Zarif (@JZarif) April 30, 2018

He also copied the photo of the graphic of a bomb that Mr Netanyahu allegedly showed during his speech at United Nations General Assembly from 2012, according to CNN.

Us President Donald Trump said in a press conference that the US will make a decision about Iran and its nuclear deal “on or before” May 12.

“In seven years, that deal will have expired and Iran is free to go ahead and create nuclear weapons. That is not acceptable. Seven years is tomorrow, that’s not acceptable. If anything, what Israel has done today in the news conference was right,” he said.

Mr Netanyahu said after his presentation, that he is sure Mr Trump will do “the right thing”.

“I’m sure he’ll do the right thing. The right thing for the US. The right thing for Israel. And the right thing for the peace of the world,” he said.

In 2015, Iran and six world powers signed the Joint Comprehensive Plan of Action (JCPOA), a commitment to curb its nuclear program and slash the number of its centrifuges, which are machines used to enrich uranium.

It also required Iran to cut its stockpile of enriched uranium drastically and not enrich remaining uranium to the level needed to produce nuclear weapons.

The agreement came after Iran was dealt crippling economic sanctions following a US National Intelligence Estimate assessment saying it believes “with high confidence” that Iran did have a nuclear weapons programme.

However, Mr Netanyahu said Iran has continued to preserve and expand its nuclear weapons knowledge for future use.

-with AAP