World leaders currently in nuclear talks with Iran should push for a stronger deal, Israeli Prime Minister Netanyahu told US lawmakers in his highly-anticipated address, stating categorically that the pending agreement would pave the way for a "potential nuclear nightmare".
In a strongly-worded speech to a joint meeting of the US Congress today, Mr Netanyahu criticised the two concessions to Iran that observers say would likely be part of the deal -the lack of any requirement that Iran destroy its nuclear facilities, and a 10-year expiry date on restrictions.
Negotiators from the ground known as the P5+1 - Britain, France, US, Russia, China and Germany - are seeking to limit Iran's capabilities without completely destroying its facilities and insisting the country submit itself to inspections.
Mr Netanyahu stressed, however, that Iran cannot properly be held in check by weapons instructors and cannot be trusted to respect the restrictions put in place, and that it also could emerge at the end of the decade of restrictions in a stronger financial position to invest in its nuclear armament.
Said Mr Netanyahu: "The first concession creates a real danger that Iran could get to the bomb by breaking the deal. The second major concession is that Iran could get to the bomb by keeping the deal."
"If anyone thinks this deal kicks the can down the road, think again. When we get down that road, we will face a much more dangerous Iran... and a countdown to a potential nuclear nightmare," he added.
The Israeli PM also dismissed the argument put forward by US President Barack Obama and others that current diplomatic efforts are better than any alternative.
Stressing that war was not the only alternative to an agreement, Mr Netanyahu said: "This is a bad deal, a very bad deal, we are better off without it. The alternative to this bad deal is a much better deal."
A better deal, he said, would involve a requirement that the nuclear restrictions not be lifted unless Iran changes its behaviour.
"If the world powers are not prepared to insist Iran change its behaviour before a deal is signed, it should at least insist Iran changes its behaviour before the deal expires… If Iran wants to be treated like a normal country, let it act like a normal country," he said.
During the nearly hour-long speech, which was also broadcast in Israel, Mr Netanyahu took pains to outline the threat posed by Iran, even comparing it to the militant group known as the Islamic State in Iraq and Syria (ISIS).
"The battle between Iran and ISIS doesn't make Iran the friend of America. Both (ISIS and Iran) want to impose a militant Islamic empire. They just disagree among themselves who will be the ruler of that empire," Mr Netanyahu said. "The enemy of your enemy is your enemy."
He added: "We must always remember, I will say it one more time, the greatest danger facing our world is the marriage of militant Islam and nuclear weapons. To defeat ISIS but let Iran get nuclear weapons would be to win the battle but lose the war."
He reiterated his warning that a nuclear Iran would pose an existential threat to the state of Israel and the Jewish people.
Though the speech in Congress puts Mr Netanyahu at loggerheads with Mr Obama, the Israeli PM did seek to cool some of the tension by affirming the strong relationship the countries have.
"We appreciate everything that President Obama has done for us all. Some of that is widely known, like strengthening security cooperation… Some of what the President has done for Israel is less well known… Some of what he does may never be known… But I know I will always be grateful to President Obama for that support," he said.
Mr Netanyahu's third address to the joint meeting of a US Congress - the only world leader since British PM Winston Churchill to do so - took place under a cloud of politics and partisanship.
The Israeli PM was invited by House Speaker John Boehner to speak without the White House or the State Department first being informed.
The event sparked a month-long diplomatic row that has soured an already tense personal relationship between Mr Obama and Mr Netanyahu.
Around 50 Democratic lawmakers boycotted the speech in Capitol Hill.
In Israel, some are also seeing the speech as an election ploy, accusing the PM of trying to use the standing ovations from US lawmakers to boost his standing at home.
Mr Netanyahu is currently locked in a close battle with the opposition ahead of polls in two weeks.
Many democratic lawmakers were quick to criticise the speech as political theatre.
House Minority leader Nancy Pelosi issued a harsh critique of the speech, accusing the Israeli leader of being condescending towards the US.
"As one who values the US-Israel relationship, and loves Israel, I was near tears throughout the Prime Minister's speech - saddened by the insult to the intelligence of the United States as part of the P5 +1 nations, and saddened by the condescension towards our knowledge of the threat posed by Iran and our broader commitment to preventing nuclear proliferation."
US President Barack Obama said he did not watch the speech, but noted that he saw "nothing new" in it from the transcript he read.
"When we shaped an interim deal (in 2013), Prime Minister Netanyahu made almost the precise same speech about how dangerous that deal was going to be," he told reporters before a meeting with Defence Secretary Ash Carter.
"And yet over a year later, even Israeli intelligence officers, and in some cases members of the Israeli government have to acknowledge that in fact, it has kept Iran from further pursuing its nuclear programme."
Mr Obama added: "The bottom line is this, we don't yet have a deal… but if we are successful negotiating then in fact this will be the best deal possible for preventing Iran from obtaining a nuclear weapon. Nothing else comes close. Sanctions won't do it, even military action won't be as successful as the deal that we have put forward."