Israeli Prime Minister Benjamin Netanyahu has said the world must stand together to stop Iran from gaining access to a nuclear weapon in his much-anticipated address to the US Congress.

"We must all stand together to stop Iran's march of conquest, subjugation and terror," Netanyahu said on Tuesday in a speech expected to escalate his campaign against US President Barack Obama's Iran diplomacy.

Netanyahu acknowledged the tension at the start of his speech and thanked Obama for his support during his time as president.


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"I know that my speech has been the subject of much controversy... That was never my intention," he said.

"The remarkable alliance of Israel and the United States has always been above politics. It must always remain above politics."

Analysis from Al Jazeera's Senior Political Analyst Marwan Bishara

Netanyahu’s supporters in Israel and the US have lots to celebrate after his speech to Congress. The prime minister sounded bold, confident and resolute. He defended what they perceive as Israel’s case against Iran, by detailing Tehran’s schemes and transgressions in the region and beyond, and elaborated on why the Iranian regime is incurable and hence any deal is a bad deal with a bad regime. 

Netanyahu’s detractors on the other hand must have rolled their eyes as he repeated the same old tired mantras and selective claims against Iran. When Netanyahu spoke about Iran defying international weapons inspectors, hiding nuclear programmes and exploiting theology to advance their interests, it sounded like he was talking about his Israel.

In reality, Netanyahu spoke of exacting tougher conditions on Iran to reach a better deal, all of which White House National Security Adviser Susan Rice said were unachievable. Hence, for all practical matters, the Israeli prime minister has left the US Congress and the world with one option only: war. 

It’s the same advice he gave Congress back in 2002 when he advocated attacking Iraq because it was amassing weapons of mass destruction. This of course turned out to be a hoax, and the war led to disastrous results for Iraq, the US and the region.

Paradoxically, the Israeli leader insisted on speaking on behalf of the Jewish people to undermine the US president. But, for whatever it's worth, Obama has garnered more Jewish support and won more Jewish votes than Netanyahu did. 

It’s not clear whether Netanyahu has changed many peoples' minds in Congress and beyond. I doubt it. But he did mount an unprecedented assault by an Israeli leader on the US president. And this will certainly have long term implications.  

If, or when, Iran meets the conditions of the P5+1 regarding its nuclear power, much of this will prove to be no more than bad history in the bilateral US-Israeli relations.

Watch more: Analysing Netanyahu's speech on Iran nuclear ambitions

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But his rhetoric quickly shifted focus to Iran - which he said could not be trusted. 

"Iran has proven time and again that it cannot be trusted," no matter what it says about permitting verification of the terms of any accord designed to prevent it from getting such weapons, he said.

"The greatest danger facing our world is the marriage of militant Islam with nuclear weapons."

'Stop agression towards neighbours'

Netanyahu said that the proposed Iran nuclear deal would leave Iran with a "vast" nuclear programme and that the world should demand that Tehran stops its agression towards its neighbours before lifting restrictions.

"It doesn't block Iran's path to the bomb, it paves Iran's path to the bomb," Netanyahu said.


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"If the deal now being negotiated is accepted by Iran, that deal will not prevent Iran from developing nuclear weapons - it will all but guarantee that Iran will get those nuclear weapons - lots of them."

Netanyahu was greeted at the US Congress by a long standing ovation.

Tuesday's address in Washington, DC has put unprecedented stress on the two leaders' relations, but Netanyahu said prior to the speech that he meant no disrespect to Obama by accepting an invitation to speak by the president's rival Republicans.

Following Netanyahu's address, Obama said he read a transcript of the remarks and found that "there was nothing new" in the speech.

He said that the Israeli leader offered no "viable alternatives" to the nuclear negotiations with Iran and that the prospect of an agreement had already resulted in a freeze and rolling back of Iran's programme.


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Iran, meanwhile, claimed the speech was part of Netanyahu's election campaign.

"The speech today by the Zionist regime's prime minister was boring and repetitive ... and part of the hardliners' election campaign in Tel Aviv," said Iran's Foreign Ministry spokeswoman Marzieh Afkham, according to state news agency IRNA. 

At least 50 Democratic members refused to attend the speech to protest against what they see as a politicisation of Israeli security, an issue on which Congress usually unites.

Netanyahu, who has played up his security credentials ahead of a closely contested March 17 election in Israel, has denied his speech would have any design other than national survival.

Al Jazeera's Imtiaz Tyab, reporting from West Jerusalem, said that the speech was expected "to go down quite well with the broader Israeli electorate, not because of the contents of his speech, but because they like seeing the Israeli PM standing before US lawmakers talking about Israel's security".

He added however that many Israelis were unhappy about the fact that Netanyahu decided to hold the speech knowing that it would cause a rift within US politics.

Netanyahu wants the Iranians stripped of nuclear projects that might be used to develop a bomb - something Tehran insists it does not want. Washington deems the Israeli demand unrealistic.

Source: Al Jazeera and agencies